X-Git-Url: http://cvs.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/51969283ec562f968d997a5581724d86d3e8b1d4..6df022667ddc1e827901913ad2afa9b7607c32ed:/armsrc/iso14443a.c

diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c
index e66a64f5..3daab199 100644
--- a/armsrc/iso14443a.c
+++ b/armsrc/iso14443a.c
@@ -1,5 +1,5 @@
-//-----------------------------------------------------------------------------
-// Merlok - June 2011
+ //-----------------------------------------------------------------------------
+// Merlok - June 2011, 2012
 // Gerhard de Koning Gans - May 2008
 // Hagen Fritsch - June 2010
 //
@@ -9,22 +9,93 @@
 //-----------------------------------------------------------------------------
 // Routines to support ISO 14443 type A.
 //-----------------------------------------------------------------------------
-
-#include "proxmark3.h"
-#include "apps.h"
-#include "util.h"
-#include "string.h"
-
-#include "iso14443crc.h"
 #include "iso14443a.h"
-#include "crapto1.h"
-#include "mifareutil.h"
 
-static uint8_t *trace = (uint8_t *) BigBuf;
-static int traceLen = 0;
-static int rsamples = 0;
-static int tracing = TRUE;
 static uint32_t iso14a_timeout;
+int rsamples = 0;
+uint8_t trigger = 0;
+// the block number for the ISO14443-4 PCB
+static uint8_t iso14_pcb_blocknum = 0;
+
+static uint8_t* free_buffer_pointer;
+
+//
+// ISO14443 timing:
+//
+// minimum time between the start bits of consecutive transfers from reader to tag: 7000 carrier (13.56Mhz) cycles
+#define REQUEST_GUARD_TIME (7000/16 + 1)
+// minimum time between last modulation of tag and next start bit from reader to tag: 1172 carrier cycles 
+#define FRAME_DELAY_TIME_PICC_TO_PCD (1172/16 + 1) 
+// bool LastCommandWasRequest = FALSE;
+
+//
+// Total delays including SSC-Transfers between ARM and FPGA. These are in carrier clock cycles (1/13,56MHz)
+//
+// When the PM acts as reader and is receiving tag data, it takes
+// 3 ticks delay in the AD converter
+// 16 ticks until the modulation detector completes and sets curbit
+// 8 ticks until bit_to_arm is assigned from curbit
+// 8*16 ticks for the transfer from FPGA to ARM
+// 4*16 ticks until we measure the time
+// - 8*16 ticks because we measure the time of the previous transfer 
+#define DELAY_AIR2ARM_AS_READER (3 + 16 + 8 + 8*16 + 4*16 - 8*16) 
+
+// When the PM acts as a reader and is sending, it takes
+// 4*16 ticks until we can write data to the sending hold register
+// 8*16 ticks until the SHR is transferred to the Sending Shift Register
+// 8 ticks until the first transfer starts
+// 8 ticks later the FPGA samples the data
+// 1 tick to assign mod_sig_coil
+#define DELAY_ARM2AIR_AS_READER (4*16 + 8*16 + 8 + 8 + 1)
+
+// When the PM acts as tag and is receiving it takes
+// 2 ticks delay in the RF part (for the first falling edge),
+// 3 ticks for the A/D conversion,
+// 8 ticks on average until the start of the SSC transfer,
+// 8 ticks until the SSC samples the first data
+// 7*16 ticks to complete the transfer from FPGA to ARM
+// 8 ticks until the next ssp_clk rising edge
+// 4*16 ticks until we measure the time 
+// - 8*16 ticks because we measure the time of the previous transfer 
+#define DELAY_AIR2ARM_AS_TAG (2 + 3 + 8 + 8 + 7*16 + 8 + 4*16 - 8*16)
+ 
+// The FPGA will report its internal sending delay in
+uint16_t FpgaSendQueueDelay;
+// the 5 first bits are the number of bits buffered in mod_sig_buf
+// the last three bits are the remaining ticks/2 after the mod_sig_buf shift
+#define DELAY_FPGA_QUEUE (FpgaSendQueueDelay<<1)
+
+// When the PM acts as tag and is sending, it takes
+// 4*16 ticks until we can write data to the sending hold register
+// 8*16 ticks until the SHR is transferred to the Sending Shift Register
+// 8 ticks until the first transfer starts
+// 8 ticks later the FPGA samples the data
+// + a varying number of ticks in the FPGA Delay Queue (mod_sig_buf)
+// + 1 tick to assign mod_sig_coil
+#define DELAY_ARM2AIR_AS_TAG (4*16 + 8*16 + 8 + 8 + DELAY_FPGA_QUEUE + 1)
+
+// When the PM acts as sniffer and is receiving tag data, it takes
+// 3 ticks A/D conversion
+// 14 ticks to complete the modulation detection
+// 8 ticks (on average) until the result is stored in to_arm
+// + the delays in transferring data - which is the same for
+// sniffing reader and tag data and therefore not relevant
+#define DELAY_TAG_AIR2ARM_AS_SNIFFER (3 + 14 + 8) 
+ 
+// When the PM acts as sniffer and is receiving reader data, it takes
+// 2 ticks delay in analogue RF receiver (for the falling edge of the 
+// start bit, which marks the start of the communication)
+// 3 ticks A/D conversion
+// 8 ticks on average until the data is stored in to_arm.
+// + the delays in transferring data - which is the same for
+// sniffing reader and tag data and therefore not relevant
+#define DELAY_READER_AIR2ARM_AS_SNIFFER (2 + 3 + 8) 
+
+//variables used for timing purposes:
+//these are in ssp_clk cycles:
+static uint32_t NextTransferTime;
+static uint32_t LastTimeProxToAirStart;
+static uint32_t LastProxToAirDuration;
 
 // CARD TO READER - manchester
 // Sequence D: 11110000 modulation with subcarrier during first half
@@ -41,569 +112,381 @@ static uint32_t iso14a_timeout;
 #define	SEC_Y 0x00
 #define	SEC_Z 0xc0
 
-static const uint8_t OddByteParity[256] = {
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0,
-  1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1
-};
-
-uint8_t trigger = 0;
-void iso14a_set_trigger(int enable) {
+void iso14a_set_trigger(bool enable) {
 	trigger = enable;
 }
 
-void iso14a_clear_tracelen(void) {
-	traceLen = 0;
+void iso14a_set_timeout(uint32_t timeout) {
+	iso14a_timeout = timeout;
+	if(MF_DBGLEVEL >= 3) Dbprintf("ISO14443A Timeout set to %ld (%dms)", iso14a_timeout, iso14a_timeout / 106);
 }
-void iso14a_set_tracing(int enable) {
-	tracing = enable;
+
+void iso14a_set_ATS_timeout(uint8_t *ats) {
+	uint8_t tb1;
+	uint8_t fwi; 
+	uint32_t fwt;
+	
+	if (ats[0] > 1) {							// there is a format byte T0
+		if ((ats[1] & 0x20) == 0x20) {			// there is an interface byte TB(1)
+
+			if ((ats[1] & 0x10) == 0x10)		// there is an interface byte TA(1) preceding TB(1)
+				tb1 = ats[3];
+			else
+				tb1 = ats[2];
+
+			fwi = (tb1 & 0xf0) >> 4;			// frame waiting indicator (FWI)
+			fwt = 256 * 16 * (1 << fwi);		// frame waiting time (FWT) in 1/fc
+			//fwt = 4096 * (1 << fwi);
+			
+			iso14a_set_timeout(fwt/(8*16));
+			//iso14a_set_timeout(fwt/128);
+		}
+	}
 }
 
 //-----------------------------------------------------------------------------
 // Generate the parity value for a byte sequence
 //
 //-----------------------------------------------------------------------------
-byte_t oddparity (const byte_t bt)
-{
-  return OddByteParity[bt];
-}
-
-uint32_t GetParity(const uint8_t * pbtCmd, int iLen)
-{
-  int i;
-  uint32_t dwPar = 0;
-
-  // Generate the encrypted data
-  for (i = 0; i < iLen; i++) {
-    // Save the encrypted parity bit
-    dwPar |= ((OddByteParity[pbtCmd[i]]) << i);
-  }
-  return dwPar;
-}
+void GetParity(const uint8_t *pbtCmd, uint16_t iLen, uint8_t *par) {
+	uint16_t paritybit_cnt = 0;
+	uint16_t paritybyte_cnt = 0;
+	uint8_t parityBits = 0;
+
+	for (uint16_t i = 0; i < iLen; i++) {
+		// Generate the parity bits
+		parityBits |= ((oddparity8(pbtCmd[i])) << (7-paritybit_cnt));
+		if (paritybit_cnt == 7) {
+			par[paritybyte_cnt] = parityBits;	// save 8 Bits parity
+			parityBits = 0;						// and advance to next Parity Byte
+			paritybyte_cnt++;
+			paritybit_cnt = 0;
+		} else {
+			paritybit_cnt++;
+		}
+	}
 
-void AppendCrc14443a(uint8_t* data, int len)
-{
-  ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1);
+	// save remaining parity bits
+	par[paritybyte_cnt] = parityBits;	
 }
 
-int LogTrace(const uint8_t * btBytes, int iLen, int iSamples, uint32_t dwParity, int bReader)
-{
-  // Return when trace is full
-  if (traceLen >= TRACE_LENGTH) return FALSE;
-
-  // Trace the random, i'm curious
-  rsamples += iSamples;
-  trace[traceLen++] = ((rsamples >> 0) & 0xff);
-  trace[traceLen++] = ((rsamples >> 8) & 0xff);
-  trace[traceLen++] = ((rsamples >> 16) & 0xff);
-  trace[traceLen++] = ((rsamples >> 24) & 0xff);
-  if (!bReader) {
-    trace[traceLen - 1] |= 0x80;
-  }
-  trace[traceLen++] = ((dwParity >> 0) & 0xff);
-  trace[traceLen++] = ((dwParity >> 8) & 0xff);
-  trace[traceLen++] = ((dwParity >> 16) & 0xff);
-  trace[traceLen++] = ((dwParity >> 24) & 0xff);
-  trace[traceLen++] = iLen;
-  memcpy(trace + traceLen, btBytes, iLen);
-  traceLen += iLen;
-  return TRUE;
+void AppendCrc14443a(uint8_t* data, int len) {
+	ComputeCrc14443(CRC_14443_A,data,len,data+len,data+len+1);
 }
 
+//=============================================================================
+// ISO 14443 Type A - Miller decoder
+//=============================================================================
+// Basics:
+// This decoder is used when the PM3 acts as a tag.
+// The reader will generate "pauses" by temporarily switching of the field. 
+// At the PM3 antenna we will therefore measure a modulated antenna voltage. 
+// The FPGA does a comparison with a threshold and would deliver e.g.:
+// ........  1 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1  .......
+// The Miller decoder needs to identify the following sequences:
+// 2 (or 3) ticks pause followed by 6 (or 5) ticks unmodulated: 	pause at beginning - Sequence Z ("start of communication" or a "0")
+// 8 ticks without a modulation: 									no pause - Sequence Y (a "0" or "end of communication" or "no information")
+// 4 ticks unmodulated followed by 2 (or 3) ticks pause:			pause in second half - Sequence X (a "1")
+// Note 1: the bitstream may start at any time. We therefore need to sync.
+// Note 2: the interpretation of Sequence Y and Z depends on the preceding sequence.
 //-----------------------------------------------------------------------------
-// The software UART that receives commands from the reader, and its state
-// variables.
-//-----------------------------------------------------------------------------
-static struct {
-    enum {
-        STATE_UNSYNCD,
-        STATE_START_OF_COMMUNICATION,
-		STATE_MILLER_X,
-		STATE_MILLER_Y,
-		STATE_MILLER_Z,
-        STATE_ERROR_WAIT
-    }       state;
-    uint16_t    shiftReg;
-    int     bitCnt;
-    int     byteCnt;
-    int     byteCntMax;
-    int     posCnt;
-    int     syncBit;
-	int     parityBits;
-	int     samples;
-    int     highCnt;
-    int     bitBuffer;
-	enum {
-		DROP_NONE,
-		DROP_FIRST_HALF,
-		DROP_SECOND_HALF
-	}		drop;
-    uint8_t   *output;
-} Uart;
-
-static RAMFUNC int MillerDecoding(int bit)
-{
-	int error = 0;
-	int bitright;
-
-	if(!Uart.bitBuffer) {
-		Uart.bitBuffer = bit ^ 0xFF0;
-		return FALSE;
-	}
-	else {
-		Uart.bitBuffer <<= 4;
-		Uart.bitBuffer ^= bit;
-	}
-
-	int EOC = FALSE;
+static tUart Uart;
+
+// Lookup-Table to decide if 4 raw bits are a modulation.
+// We accept the following:
+// 0001  -   a 3 tick wide pause
+// 0011  -   a 2 tick wide pause, or a three tick wide pause shifted left
+// 0111  -   a 2 tick wide pause shifted left
+// 1001  -   a 2 tick wide pause shifted right
+const bool Mod_Miller_LUT[] = {
+	FALSE,  TRUE, FALSE, TRUE,  FALSE, FALSE, FALSE, TRUE,
+	FALSE,  TRUE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE
+};
+#define IsMillerModulationNibble1(b) (Mod_Miller_LUT[(b & 0x000000F0) >> 4])
+#define IsMillerModulationNibble2(b) (Mod_Miller_LUT[(b & 0x0000000F)])
 
-	if(Uart.state != STATE_UNSYNCD) {
-		Uart.posCnt++;
+void UartReset() {
+	Uart.state = STATE_UNSYNCD;
+	Uart.bitCount = 0;
+	Uart.len = 0;						// number of decoded data bytes
+	Uart.parityLen = 0;					// number of decoded parity bytes
+	Uart.shiftReg = 0;					// shiftreg to hold decoded data bits
+	Uart.parityBits = 0;				// holds 8 parity bits
+	Uart.startTime = 0;
+	Uart.endTime = 0;
+	
+	Uart.byteCntMax = 0;
+	Uart.posCnt = 0;
+	Uart.syncBit = 9999;
+}
 
-		if((Uart.bitBuffer & Uart.syncBit) ^ Uart.syncBit) {
-			bit = 0x00;
-		}
-		else {
-			bit = 0x01;
-		}
-		if(((Uart.bitBuffer << 1) & Uart.syncBit) ^ Uart.syncBit) {
-			bitright = 0x00;
-		}
-		else {
-			bitright = 0x01;
-		}
-		if(bit != bitright) { bit = bitright; }
+void UartInit(uint8_t *data, uint8_t *parity) {
+	Uart.output = data;
+	Uart.parity = parity;
+	Uart.fourBits = 0x00000000;			// clear the buffer for 4 Bits
+	UartReset();
+}
 
-		if(Uart.posCnt == 1) {
-			// measurement first half bitperiod
-			if(!bit) {
-				Uart.drop = DROP_FIRST_HALF;
-			}
+// use parameter non_real_time to provide a timestamp. Set to 0 if the decoder should measure real time
+static RAMFUNC bool MillerDecoding(uint8_t bit, uint32_t non_real_time) {
+	Uart.fourBits = (Uart.fourBits << 8) | bit;
+	
+	if (Uart.state == STATE_UNSYNCD) {											// not yet synced
+			Uart.syncBit = 9999; 												// not set
+		
+		// 00x11111 2|3 ticks pause followed by 6|5 ticks unmodulated	 	Sequence Z (a "0" or "start of communication")
+		// 11111111 8 ticks unmodulation									Sequence Y (a "0" or "end of communication" or "no information")
+		// 111100x1 4 ticks unmodulated followed by 2|3 ticks pause			Sequence X (a "1")
+
+		// The start bit is one ore more Sequence Y followed by a Sequence Z (... 11111111 00x11111). We need to distinguish from
+		// Sequence X followed by Sequence Y followed by Sequence Z     (111100x1 11111111 00x11111)
+		// we therefore look for a ...xx1111 11111111 00x11111xxxxxx... pattern 
+		// (12 '1's followed by 2 '0's, eventually followed by another '0', followed by 5 '1's)
+		//
+#define ISO14443A_STARTBIT_MASK		0x07FFEF80		// mask is    00001111 11111111 1110 1111 10000000
+#define ISO14443A_STARTBIT_PATTERN	0x07FF8F80		// pattern is 00001111 11111111 1000 1111 10000000
+
+		if		((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 0)) == ISO14443A_STARTBIT_PATTERN >> 0) Uart.syncBit = 7;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 1)) == ISO14443A_STARTBIT_PATTERN >> 1) Uart.syncBit = 6;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 2)) == ISO14443A_STARTBIT_PATTERN >> 2) Uart.syncBit = 5;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 3)) == ISO14443A_STARTBIT_PATTERN >> 3) Uart.syncBit = 4;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 4)) == ISO14443A_STARTBIT_PATTERN >> 4) Uart.syncBit = 3;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 5)) == ISO14443A_STARTBIT_PATTERN >> 5) Uart.syncBit = 2;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 6)) == ISO14443A_STARTBIT_PATTERN >> 6) Uart.syncBit = 1;
+		else if ((Uart.fourBits & (ISO14443A_STARTBIT_MASK >> 7)) == ISO14443A_STARTBIT_PATTERN >> 7) Uart.syncBit = 0;
+
+		if (Uart.syncBit != 9999) {												// found a sync bit
+			Uart.startTime = non_real_time ? non_real_time : (GetCountSspClk() & 0xfffffff8);
+			Uart.startTime -= Uart.syncBit;
+			Uart.endTime = Uart.startTime;
+			Uart.state = STATE_START_OF_COMMUNICATION;
 		}
-		else {
-			// measurement second half bitperiod
-			if(!bit & (Uart.drop == DROP_NONE)) {
-				Uart.drop = DROP_SECOND_HALF;
-			}
-			else if(!bit) {
-				// measured a drop in first and second half
-				// which should not be possible
-				Uart.state = STATE_ERROR_WAIT;
-				error = 0x01;
+	} else {
+
+		if (IsMillerModulationNibble1(Uart.fourBits >> Uart.syncBit)) {			
+			if (IsMillerModulationNibble2(Uart.fourBits >> Uart.syncBit)) {		// Modulation in both halves - error
+				UartReset();
+			} else {															// Modulation in first half = Sequence Z = logic "0"
+				if (Uart.state == STATE_MILLER_X) {								// error - must not follow after X
+					UartReset();
+				} else {
+					Uart.bitCount++;
+					Uart.shiftReg = (Uart.shiftReg >> 1);						// add a 0 to the shiftreg
+					Uart.state = STATE_MILLER_Z;
+					Uart.endTime = Uart.startTime + 8*(9*Uart.len + Uart.bitCount + 1) - 6;
+					if(Uart.bitCount >= 9) {									// if we decoded a full byte (including parity)
+						Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);
+						Uart.parityBits <<= 1;									// make room for the parity bit
+						Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01);		// store parity bit
+						Uart.bitCount = 0;
+						Uart.shiftReg = 0;
+						if((Uart.len&0x0007) == 0) {							// every 8 data bytes
+							Uart.parity[Uart.parityLen++] = Uart.parityBits;	// store 8 parity bits
+							Uart.parityBits = 0;
+						}
+					}
+				}
 			}
-
-			Uart.posCnt = 0;
-
-			switch(Uart.state) {
-				case STATE_START_OF_COMMUNICATION:
+		} else {
+			if (IsMillerModulationNibble2(Uart.fourBits >> Uart.syncBit)) {		// Modulation second half = Sequence X = logic "1"
+				Uart.bitCount++;
+				Uart.shiftReg = (Uart.shiftReg >> 1) | 0x100;					// add a 1 to the shiftreg
+				Uart.state = STATE_MILLER_X;
+				Uart.endTime = Uart.startTime + 8*(9*Uart.len + Uart.bitCount + 1) - 2;
+				if(Uart.bitCount >= 9) {										// if we decoded a full byte (including parity)
+					Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);
+					Uart.parityBits <<= 1;										// make room for the new parity bit
+					Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01); 			// store parity bit
+					Uart.bitCount = 0;
 					Uart.shiftReg = 0;
-					if(Uart.drop == DROP_SECOND_HALF) {
-						// error, should not happen in SOC
-						Uart.state = STATE_ERROR_WAIT;
-						error = 0x02;
-					}
-					else {
-						// correct SOC
-						Uart.state = STATE_MILLER_Z;
-					}
-					break;
-
-				case STATE_MILLER_Z:
-					Uart.bitCnt++;
-					Uart.shiftReg >>= 1;
-					if(Uart.drop == DROP_NONE) {
-						// logic '0' followed by sequence Y
-						// end of communication
-						Uart.state = STATE_UNSYNCD;
-						EOC = TRUE;
-					}
-					// if(Uart.drop == DROP_FIRST_HALF) {
-					// 	Uart.state = STATE_MILLER_Z; stay the same
-					// 	we see a logic '0' }
-					if(Uart.drop == DROP_SECOND_HALF) {
-						// we see a logic '1'
-						Uart.shiftReg |= 0x100;
-						Uart.state = STATE_MILLER_X;
-					}
-					break;
-
-				case STATE_MILLER_X:
-					Uart.shiftReg >>= 1;
-					if(Uart.drop == DROP_NONE) {
-						// sequence Y, we see a '0'
-						Uart.state = STATE_MILLER_Y;
-						Uart.bitCnt++;
-					}
-					if(Uart.drop == DROP_FIRST_HALF) {
-						// Would be STATE_MILLER_Z
-						// but Z does not follow X, so error
-						Uart.state = STATE_ERROR_WAIT;
-						error = 0x03;
-					}
-					if(Uart.drop == DROP_SECOND_HALF) {
-						// We see a '1' and stay in state X
-						Uart.shiftReg |= 0x100;
-						Uart.bitCnt++;
+					if ((Uart.len&0x0007) == 0) {								// every 8 data bytes
+						Uart.parity[Uart.parityLen++] = Uart.parityBits;		// store 8 parity bits
+						Uart.parityBits = 0;
 					}
-					break;
-
-				case STATE_MILLER_Y:
-					Uart.bitCnt++;
-					Uart.shiftReg >>= 1;
-					if(Uart.drop == DROP_NONE) {
-						// logic '0' followed by sequence Y
-						// end of communication
-						Uart.state = STATE_UNSYNCD;
-						EOC = TRUE;
-					}
-					if(Uart.drop == DROP_FIRST_HALF) {
-						// we see a '0'
-						Uart.state = STATE_MILLER_Z;
-					}
-					if(Uart.drop == DROP_SECOND_HALF) {
-						// We see a '1' and go to state X
-						Uart.shiftReg |= 0x100;
-						Uart.state = STATE_MILLER_X;
+				}
+			} else {															// no modulation in both halves - Sequence Y
+				if (Uart.state == STATE_MILLER_Z || Uart.state == STATE_MILLER_Y) {	// Y after logic "0" - End of Communication
+					Uart.state = STATE_UNSYNCD;
+					Uart.bitCount--;											// last "0" was part of EOC sequence
+					Uart.shiftReg <<= 1;										// drop it
+					if(Uart.bitCount > 0) {										// if we decoded some bits
+						Uart.shiftReg >>= (9 - Uart.bitCount);					// right align them
+						Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);		// add last byte to the output
+						Uart.parityBits <<= 1;									// add a (void) parity bit
+						Uart.parityBits <<= (8 - (Uart.len&0x0007));			// left align parity bits
+						Uart.parity[Uart.parityLen++] = Uart.parityBits;		// and store it
+						return TRUE;
+					} else if (Uart.len & 0x0007) {								// there are some parity bits to store
+						Uart.parityBits <<= (8 - (Uart.len&0x0007));			// left align remaining parity bits
+						Uart.parity[Uart.parityLen++] = Uart.parityBits;		// and store them
 					}
-					break;
-
-				case STATE_ERROR_WAIT:
-					// That went wrong. Now wait for at least two bit periods
-					// and try to sync again
-					if(Uart.drop == DROP_NONE) {
-						Uart.highCnt = 6;
-						Uart.state = STATE_UNSYNCD;
+					if (Uart.len) {
+						return TRUE;											// we are finished with decoding the raw data sequence
+					} else {
+						UartReset();											// Nothing received - start over
 					}
-					break;
-
-				default:
-					Uart.state = STATE_UNSYNCD;
-					Uart.highCnt = 0;
-					break;
-			}
-
-			Uart.drop = DROP_NONE;
-
-			// should have received at least one whole byte...
-			if((Uart.bitCnt == 2) && EOC && (Uart.byteCnt > 0)) {
-				return TRUE;
-			}
-
-			if(Uart.bitCnt == 9) {
-				Uart.output[Uart.byteCnt] = (Uart.shiftReg & 0xff);
-				Uart.byteCnt++;
-
-				Uart.parityBits <<= 1;
-				Uart.parityBits ^= ((Uart.shiftReg >> 8) & 0x01);
-
-				if(EOC) {
-					// when End of Communication received and
-					// all data bits processed..
-					return TRUE;
 				}
-				Uart.bitCnt = 0;
-			}
-
-			/*if(error) {
-				Uart.output[Uart.byteCnt] = 0xAA;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = error & 0xFF;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = 0xAA;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = (Uart.bitBuffer >> 8) & 0xFF;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = Uart.bitBuffer & 0xFF;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = (Uart.syncBit >> 3) & 0xFF;
-				Uart.byteCnt++;
-				Uart.output[Uart.byteCnt] = 0xAA;
-				Uart.byteCnt++;
-				return TRUE;
-			}*/
-		}
-
-	}
-	else {
-		bit = Uart.bitBuffer & 0xf0;
-		bit >>= 4;
-		bit ^= 0x0F;
-		if(bit) {
-			// should have been high or at least (4 * 128) / fc
-			// according to ISO this should be at least (9 * 128 + 20) / fc
-			if(Uart.highCnt == 8) {
-				// we went low, so this could be start of communication
-				// it turns out to be safer to choose a less significant
-				// syncbit... so we check whether the neighbour also represents the drop
-				Uart.posCnt = 1;   // apparently we are busy with our first half bit period
-				Uart.syncBit = bit & 8;
-				Uart.samples = 3;
-				if(!Uart.syncBit)	{ Uart.syncBit = bit & 4; Uart.samples = 2; }
-				else if(bit & 4)	{ Uart.syncBit = bit & 4; Uart.samples = 2; bit <<= 2; }
-				if(!Uart.syncBit)	{ Uart.syncBit = bit & 2; Uart.samples = 1; }
-				else if(bit & 2)	{ Uart.syncBit = bit & 2; Uart.samples = 1; bit <<= 1; }
-				if(!Uart.syncBit)	{ Uart.syncBit = bit & 1; Uart.samples = 0;
-					if(Uart.syncBit && (Uart.bitBuffer & 8)) {
-						Uart.syncBit = 8;
-
-						// the first half bit period is expected in next sample
-						Uart.posCnt = 0;
-						Uart.samples = 3;
+				if (Uart.state == STATE_START_OF_COMMUNICATION) {				// error - must not follow directly after SOC
+					UartReset();
+				} else {														// a logic "0"
+					Uart.bitCount++;
+					Uart.shiftReg = (Uart.shiftReg >> 1);						// add a 0 to the shiftreg
+					Uart.state = STATE_MILLER_Y;
+					if(Uart.bitCount >= 9) {									// if we decoded a full byte (including parity)
+						Uart.output[Uart.len++] = (Uart.shiftReg & 0xff);
+						Uart.parityBits <<= 1;									// make room for the parity bit
+						Uart.parityBits |= ((Uart.shiftReg >> 8) & 0x01); 		// store parity bit
+						Uart.bitCount = 0;
+						Uart.shiftReg = 0;
+						if ((Uart.len&0x0007) == 0) {							// every 8 data bytes
+							Uart.parity[Uart.parityLen++] = Uart.parityBits;	// store 8 parity bits
+							Uart.parityBits = 0;
+						}
 					}
 				}
-				else if(bit & 1)	{ Uart.syncBit = bit & 1; Uart.samples = 0; }
-
-				Uart.syncBit <<= 4;
-				Uart.state = STATE_START_OF_COMMUNICATION;
-				Uart.drop = DROP_FIRST_HALF;
-				Uart.bitCnt = 0;
-				Uart.byteCnt = 0;
-				Uart.parityBits = 0;
-				error = 0;
-			}
-			else {
-				Uart.highCnt = 0;
-			}
-		}
-		else {
-			if(Uart.highCnt < 8) {
-				Uart.highCnt++;
 			}
 		}
-	}
-
-    return FALSE;
+	} 
+    return FALSE;	// not finished yet, need more data
 }
 
 //=============================================================================
-// ISO 14443 Type A - Manchester
+// ISO 14443 Type A - Manchester decoder
 //=============================================================================
+// Basics:
+// This decoder is used when the PM3 acts as a reader.
+// The tag will modulate the reader field by asserting different loads to it. As a consequence, the voltage
+// at the reader antenna will be modulated as well. The FPGA detects the modulation for us and would deliver e.g. the following:
+// ........ 0 0 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 .......
+// The Manchester decoder needs to identify the following sequences:
+// 4 ticks modulated followed by 4 ticks unmodulated: 	Sequence D = 1 (also used as "start of communication")
+// 4 ticks unmodulated followed by 4 ticks modulated: 	Sequence E = 0
+// 8 ticks unmodulated:									Sequence F = end of communication
+// 8 ticks modulated:									A collision. Save the collision position and treat as Sequence D
+// Note 1: the bitstream may start at any time. We therefore need to sync.
+// Note 2: parameter offset is used to determine the position of the parity bits (required for the anticollision command only)
+static tDemod Demod;
+
+// Lookup-Table to decide if 4 raw bits are a modulation.
+// We accept three or four "1" in any position
+const bool Mod_Manchester_LUT[] = {
+	FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, TRUE,
+	FALSE, FALSE, FALSE, TRUE,  FALSE, TRUE,  TRUE,  TRUE
+};
 
-static struct {
-    enum {
-        DEMOD_UNSYNCD,
-		DEMOD_START_OF_COMMUNICATION,
-		DEMOD_MANCHESTER_D,
-		DEMOD_MANCHESTER_E,
-		DEMOD_MANCHESTER_F,
-        DEMOD_ERROR_WAIT
-    }       state;
-    int     bitCount;
-    int     posCount;
-	int     syncBit;
-	int     parityBits;
-    uint16_t    shiftReg;
-	int     buffer;
-	int     buff;
-	int     samples;
-    int     len;
-	enum {
-		SUB_NONE,
-		SUB_FIRST_HALF,
-		SUB_SECOND_HALF
-	}		sub;
-    uint8_t   *output;
-} Demod;
-
-static RAMFUNC int ManchesterDecoding(int v)
-{
-	int bit;
-	int modulation;
-	int error = 0;
+#define IsManchesterModulationNibble1(b) (Mod_Manchester_LUT[(b & 0x00F0) >> 4])
+#define IsManchesterModulationNibble2(b) (Mod_Manchester_LUT[(b & 0x000F)])
 
-	if(!Demod.buff) {
-		Demod.buff = 1;
-		Demod.buffer = v;
-		return FALSE;
-	}
-	else {
-		bit = Demod.buffer;
-		Demod.buffer = v;
-	}
+void DemodReset() {
+	Demod.state = DEMOD_UNSYNCD;
+	Demod.len = 0;						// number of decoded data bytes
+	Demod.parityLen = 0;
+	Demod.shiftReg = 0;					// shiftreg to hold decoded data bits
+	Demod.parityBits = 0;				// 
+	Demod.collisionPos = 0;				// Position of collision bit
+	Demod.twoBits = 0xffff;				// buffer for 2 Bits
+	Demod.highCnt = 0;
+	Demod.startTime = 0;
+	Demod.endTime = 0;	
+	Demod.bitCount = 0;
+	Demod.syncBit = 0xFFFF;
+	Demod.samples = 0;
+}
 
-	if(Demod.state==DEMOD_UNSYNCD) {
-		Demod.output[Demod.len] = 0xfa;
-		Demod.syncBit = 0;
-		//Demod.samples = 0;
-		Demod.posCount = 1;		// This is the first half bit period, so after syncing handle the second part
+void DemodInit(uint8_t *data, uint8_t *parity) {
+	Demod.output = data;
+	Demod.parity = parity;
+	DemodReset();
+}
 
-		if(bit & 0x08) {
-			Demod.syncBit = 0x08;
-		}
+// use parameter non_real_time to provide a timestamp. Set to 0 if the decoder should measure real time
+static RAMFUNC int ManchesterDecoding(uint8_t bit, uint16_t offset, uint32_t non_real_time) {
+	Demod.twoBits = (Demod.twoBits << 8) | bit;
+	
+	if (Demod.state == DEMOD_UNSYNCD) {
 
-		if(bit & 0x04) {
-			if(Demod.syncBit) {
-				bit <<= 4;
+		if (Demod.highCnt < 2) {											// wait for a stable unmodulated signal
+			if (Demod.twoBits == 0x0000) {
+				Demod.highCnt++;
+			} else {
+				Demod.highCnt = 0;
 			}
-			Demod.syncBit = 0x04;
-		}
-
-		if(bit & 0x02) {
-			if(Demod.syncBit) {
-				bit <<= 2;
+		} else {
+			Demod.syncBit = 0xFFFF;			// not set
+			if 		((Demod.twoBits & 0x7700) == 0x7000) Demod.syncBit = 7; 
+			else if ((Demod.twoBits & 0x3B80) == 0x3800) Demod.syncBit = 6;
+			else if ((Demod.twoBits & 0x1DC0) == 0x1C00) Demod.syncBit = 5;
+			else if ((Demod.twoBits & 0x0EE0) == 0x0E00) Demod.syncBit = 4;
+			else if ((Demod.twoBits & 0x0770) == 0x0700) Demod.syncBit = 3;
+			else if ((Demod.twoBits & 0x03B8) == 0x0380) Demod.syncBit = 2;
+			else if ((Demod.twoBits & 0x01DC) == 0x01C0) Demod.syncBit = 1;
+			else if ((Demod.twoBits & 0x00EE) == 0x00E0) Demod.syncBit = 0;
+			if (Demod.syncBit != 0xFFFF) {
+				Demod.startTime = non_real_time?non_real_time:(GetCountSspClk() & 0xfffffff8);
+				Demod.startTime -= Demod.syncBit;
+				Demod.bitCount = offset;			// number of decoded data bits
+				Demod.state = DEMOD_MANCHESTER_DATA;
 			}
-			Demod.syncBit = 0x02;
 		}
+	} else {
 
-		if(bit & 0x01 && Demod.syncBit) {
-			Demod.syncBit = 0x01;
-		}
-		
-		if(Demod.syncBit) {
-			Demod.len = 0;
-			Demod.state = DEMOD_START_OF_COMMUNICATION;
-			Demod.sub = SUB_FIRST_HALF;
-			Demod.bitCount = 0;
-			Demod.shiftReg = 0;
-			Demod.parityBits = 0;
-			Demod.samples = 0;
-			if(Demod.posCount) {
-				if(trigger) LED_A_OFF();
-				switch(Demod.syncBit) {
-					case 0x08: Demod.samples = 3; break;
-					case 0x04: Demod.samples = 2; break;
-					case 0x02: Demod.samples = 1; break;
-					case 0x01: Demod.samples = 0; break;
+		if (IsManchesterModulationNibble1(Demod.twoBits >> Demod.syncBit)) {		// modulation in first half
+			if (IsManchesterModulationNibble2(Demod.twoBits >> Demod.syncBit)) {	// ... and in second half = collision
+				if (!Demod.collisionPos) {
+					Demod.collisionPos = (Demod.len << 3) + Demod.bitCount;
 				}
-			}
-			error = 0;
-		}
-	}
-	else {
-		//modulation = bit & Demod.syncBit;
-		modulation = ((bit << 1) ^ ((Demod.buffer & 0x08) >> 3)) & Demod.syncBit;
-
-		Demod.samples += 4;
-
-		if(Demod.posCount==0) {
-			Demod.posCount = 1;
-			if(modulation) {
-				Demod.sub = SUB_FIRST_HALF;
-			}
-			else {
-				Demod.sub = SUB_NONE;
-			}
-		}
-		else {
-			Demod.posCount = 0;
-			if(modulation && (Demod.sub == SUB_FIRST_HALF)) {
-				if(Demod.state!=DEMOD_ERROR_WAIT) {
-					Demod.state = DEMOD_ERROR_WAIT;
-					Demod.output[Demod.len] = 0xaa;
-					error = 0x01;
+			}															// modulation in first half only - Sequence D = 1
+			Demod.bitCount++;
+			Demod.shiftReg = (Demod.shiftReg >> 1) | 0x100;				// in both cases, add a 1 to the shiftreg
+			if(Demod.bitCount == 9) {									// if we decoded a full byte (including parity)
+				Demod.output[Demod.len++] = (Demod.shiftReg & 0xff);
+				Demod.parityBits <<= 1;									// make room for the parity bit
+				Demod.parityBits |= ((Demod.shiftReg >> 8) & 0x01); 	// store parity bit
+				Demod.bitCount = 0;
+				Demod.shiftReg = 0;
+				if((Demod.len&0x0007) == 0) {							// every 8 data bytes
+					Demod.parity[Demod.parityLen++] = Demod.parityBits;	// store 8 parity bits
+					Demod.parityBits = 0;
 				}
 			}
-			else if(modulation) {
-				Demod.sub = SUB_SECOND_HALF;
-			}
-
-			switch(Demod.state) {
-				case DEMOD_START_OF_COMMUNICATION:
-					if(Demod.sub == SUB_FIRST_HALF) {
-						Demod.state = DEMOD_MANCHESTER_D;
-					}
-					else {
-						Demod.output[Demod.len] = 0xab;
-						Demod.state = DEMOD_ERROR_WAIT;
-						error = 0x02;
-					}
-					break;
-
-				case DEMOD_MANCHESTER_D:
-				case DEMOD_MANCHESTER_E:
-					if(Demod.sub == SUB_FIRST_HALF) {
-						Demod.bitCount++;
-						Demod.shiftReg = (Demod.shiftReg >> 1) ^ 0x100;
-						Demod.state = DEMOD_MANCHESTER_D;
-					}
-					else if(Demod.sub == SUB_SECOND_HALF) {
-						Demod.bitCount++;
-						Demod.shiftReg >>= 1;
-						Demod.state = DEMOD_MANCHESTER_E;
-					}
-					else {
-						Demod.state = DEMOD_MANCHESTER_F;
-					}
-					break;
-
-				case DEMOD_MANCHESTER_F:
-					// Tag response does not need to be a complete byte!
-					if(Demod.len > 0 || Demod.bitCount > 0) {
-						if(Demod.bitCount > 0) {
-							Demod.shiftReg >>= (9 - Demod.bitCount);
-							Demod.output[Demod.len] = Demod.shiftReg & 0xff;
-							Demod.len++;
-							// No parity bit, so just shift a 0
-							Demod.parityBits <<= 1;
-						}
-
-						Demod.state = DEMOD_UNSYNCD;
-						return TRUE;
-					}
-					else {
-						Demod.output[Demod.len] = 0xad;
-						Demod.state = DEMOD_ERROR_WAIT;
-						error = 0x03;
+			Demod.endTime = Demod.startTime + 8*(9*Demod.len + Demod.bitCount + 1) - 4;
+		} else {														// no modulation in first half
+			if (IsManchesterModulationNibble2(Demod.twoBits >> Demod.syncBit)) {	// and modulation in second half = Sequence E = 0
+				Demod.bitCount++;
+				Demod.shiftReg = (Demod.shiftReg >> 1);					// add a 0 to the shiftreg
+				if(Demod.bitCount >= 9) {								// if we decoded a full byte (including parity)
+					Demod.output[Demod.len++] = (Demod.shiftReg & 0xff);
+					Demod.parityBits <<= 1;								// make room for the new parity bit
+					Demod.parityBits |= ((Demod.shiftReg >> 8) & 0x01); // store parity bit
+					Demod.bitCount = 0;
+					Demod.shiftReg = 0;
+					if ((Demod.len&0x0007) == 0) {						// every 8 data bytes
+						Demod.parity[Demod.parityLen++] = Demod.parityBits;	// store 8 parity bits1
+						Demod.parityBits = 0;
 					}
-					break;
-
-				case DEMOD_ERROR_WAIT:
-					Demod.state = DEMOD_UNSYNCD;
-					break;
-
-				default:
-					Demod.output[Demod.len] = 0xdd;
-					Demod.state = DEMOD_UNSYNCD;
-					break;
-			}
-
-			if(Demod.bitCount>=9) {
-				Demod.output[Demod.len] = Demod.shiftReg & 0xff;
-				Demod.len++;
-
-				Demod.parityBits <<= 1;
-				Demod.parityBits ^= ((Demod.shiftReg >> 8) & 0x01);
-
-				Demod.bitCount = 0;
-				Demod.shiftReg = 0;
+				}
+				Demod.endTime = Demod.startTime + 8*(9*Demod.len + Demod.bitCount + 1);
+			} else {													// no modulation in both halves - End of communication
+				if(Demod.bitCount > 0) {								// there are some remaining data bits
+					Demod.shiftReg >>= (9 - Demod.bitCount);			// right align the decoded bits
+					Demod.output[Demod.len++] = Demod.shiftReg & 0xff;	// and add them to the output
+					Demod.parityBits <<= 1;								// add a (void) parity bit
+					Demod.parityBits <<= (8 - (Demod.len&0x0007));		// left align remaining parity bits
+					Demod.parity[Demod.parityLen++] = Demod.parityBits;	// and store them
+					return TRUE;
+				} else if (Demod.len & 0x0007) {						// there are some parity bits to store
+					Demod.parityBits <<= (8 - (Demod.len&0x0007));		// left align remaining parity bits
+					Demod.parity[Demod.parityLen++] = Demod.parityBits;	// and store them
+				}
+				if (Demod.len) {
+					return TRUE;										// we are finished with decoding the raw data sequence
+				} else { 												// nothing received. Start over
+					DemodReset();
+				}
 			}
-
-			/*if(error) {
-				Demod.output[Demod.len] = 0xBB;
-				Demod.len++;
-				Demod.output[Demod.len] = error & 0xFF;
-				Demod.len++;
-				Demod.output[Demod.len] = 0xBB;
-				Demod.len++;
-				Demod.output[Demod.len] = bit & 0xFF;
-				Demod.len++;
-				Demod.output[Demod.len] = Demod.buffer & 0xFF;
-				Demod.len++;
-				Demod.output[Demod.len] = Demod.syncBit & 0xFF;
-				Demod.len++;
-				Demod.output[Demod.len] = 0xBB;
-				Demod.len++;
-				return TRUE;
-			}*/
-
 		}
-
-	} // end (state != UNSYNCED)
-
-    return FALSE;
+	} 
+    return FALSE;	// not finished yet, need more data
 }
 
 //=============================================================================
@@ -615,180 +498,174 @@ static RAMFUNC int ManchesterDecoding(int v)
 // Record the sequence of commands sent by the reader to the tag, with
 // triggering so that we start recording at the point that the tag is moved
 // near the reader.
+// "hf 14a sniff"
 //-----------------------------------------------------------------------------
-void RAMFUNC SnoopIso14443a(void)
-{
-//	#define RECV_CMD_OFFSET 	2032	// original (working as of 21/2/09) values
-//	#define RECV_RES_OFFSET		2096	// original (working as of 21/2/09) values
-//	#define DMA_BUFFER_OFFSET	2160	// original (working as of 21/2/09) values
-//	#define DMA_BUFFER_SIZE 	4096	// original (working as of 21/2/09) values
-//	#define TRACE_LENGTH	 	2000	// original (working as of 21/2/09) values
-
-    // We won't start recording the frames that we acquire until we trigger;
-    // a good trigger condition to get started is probably when we see a
-    // response from the tag.
-    int triggered = FALSE; // FALSE to wait first for card
-
-    // The command (reader -> tag) that we're receiving.
-	// The length of a received command will in most cases be no more than 18 bytes.
-	// So 32 should be enough!
-    uint8_t *receivedCmd = (((uint8_t *)BigBuf) + RECV_CMD_OFFSET);
-    // The response (tag -> reader) that we're receiving.
-    uint8_t *receivedResponse = (((uint8_t *)BigBuf) + RECV_RES_OFFSET);
-
-    // As we receive stuff, we copy it from receivedCmd or receivedResponse
-    // into trace, along with its length and other annotations.
-    //uint8_t *trace = (uint8_t *)BigBuf;
-    
-    traceLen = 0; // uncommented to fix ISSUE 15 - gerhard - jan2011
-
-    // The DMA buffer, used to stream samples from the FPGA
-    int8_t *dmaBuf = ((int8_t *)BigBuf) + DMA_BUFFER_OFFSET;
-    int lastRxCounter;
-    int8_t *upTo;
-    int smpl;
-    int maxBehindBy = 0;
-
-    // Count of samples received so far, so that we can include timing
-    // information in the trace buffer.
-    int samples = 0;
-    int rsamples = 0;
-
-    memset(trace, 0x44, RECV_CMD_OFFSET);
-
-    // Set up the demodulator for tag -> reader responses.
-    Demod.output = receivedResponse;
-    Demod.len = 0;
-    Demod.state = DEMOD_UNSYNCD;
-
-    // Setup for the DMA.
-    FpgaSetupSsc();
-    upTo = dmaBuf;
-    lastRxCounter = DMA_BUFFER_SIZE;
-    FpgaSetupSscDma((uint8_t *)dmaBuf, DMA_BUFFER_SIZE);
-
-    // And the reader -> tag commands
-    memset(&Uart, 0, sizeof(Uart));
-    Uart.output = receivedCmd;
-    Uart.byteCntMax = 32; // was 100 (greg)////////////////////////////////////////////////////////////////////////
-    Uart.state = STATE_UNSYNCD;
-
-    // And put the FPGA in the appropriate mode
-    // Signal field is off with the appropriate LED
-    LED_D_OFF();
-    FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_SNIFFER);
-    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+void RAMFUNC SniffIso14443a(uint8_t param) {
+	// param:
+	// bit 0 - trigger from first card answer
+	// bit 1 - trigger from first reader 7-bit request
+	LEDsoff();
 
+	iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
+	
+	// Allocate memory from BigBuf for some buffers
+	// free all previous allocations first
+	BigBuf_free(); BigBuf_Clear_ext(false);
+	clear_trace();
+	set_tracing(TRUE);
+	
+	// The command (reader -> tag) that we're receiving.
+	uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
+	uint8_t *receivedCmdPar = BigBuf_malloc(MAX_PARITY_SIZE);
+	
+	// The response (tag -> reader) that we're receiving.
+	uint8_t *receivedResponse = BigBuf_malloc(MAX_FRAME_SIZE);
+	uint8_t *receivedResponsePar = BigBuf_malloc(MAX_PARITY_SIZE);
+	
+	// The DMA buffer, used to stream samples from the FPGA
+	uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
+
+	uint8_t *data = dmaBuf;
+	uint8_t previous_data = 0;
+	int maxDataLen = 0;
+	int dataLen = 0;
+	bool TagIsActive = FALSE;
+	bool ReaderIsActive = FALSE;
+	
+	// Set up the demodulator for tag -> reader responses.
+	DemodInit(receivedResponse, receivedResponsePar);
+	
+	// Set up the demodulator for the reader -> tag commands
+	UartInit(receivedCmd, receivedCmdPar);
+	
+	// Setup and start DMA.
+	if ( !FpgaSetupSscDma((uint8_t*) dmaBuf, DMA_BUFFER_SIZE) ){
+		if (MF_DBGLEVEL > 1) Dbprintf("FpgaSetupSscDma failed. Exiting"); 
+		return;
+	}
+	
+	// We won't start recording the frames that we acquire until we trigger;
+	// a good trigger condition to get started is probably when we see a
+	// response from the tag.
+	// triggered == FALSE -- to wait first for card
+	bool triggered = !(param & 0x03); 
+	
+	// And now we loop, receiving samples.
+	for(uint32_t rsamples = 0; TRUE; ) {
 
-    // And now we loop, receiving samples.
-    for(;;) {
-        LED_A_ON();
-        WDT_HIT();
-        int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) &
-                                (DMA_BUFFER_SIZE-1);
-        if(behindBy > maxBehindBy) {
-            maxBehindBy = behindBy;
-            if(behindBy > 400) {
-                Dbprintf("blew circular buffer! behindBy=0x%x", behindBy);
-                goto done;
-            }
-        }
-        if(behindBy < 1) continue;
+		if(BUTTON_PRESS()) {
+			DbpString("cancelled by button");
+			break;
+		}
 
-	LED_A_OFF();
-        smpl = upTo[0];
-        upTo++;
-        lastRxCounter -= 1;
-        if(upTo - dmaBuf > DMA_BUFFER_SIZE) {
-            upTo -= DMA_BUFFER_SIZE;
-            lastRxCounter += DMA_BUFFER_SIZE;
-            AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
-            AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
-        }
+		LED_A_ON();
+		WDT_HIT();
 
-        samples += 4;
-        if(MillerDecoding((smpl & 0xF0) >> 4)) {
-            rsamples = samples - Uart.samples;
-            LED_C_ON();
-            if(triggered) {
-                trace[traceLen++] = ((rsamples >>  0) & 0xff);
-                trace[traceLen++] = ((rsamples >>  8) & 0xff);
-                trace[traceLen++] = ((rsamples >> 16) & 0xff);
-                trace[traceLen++] = ((rsamples >> 24) & 0xff);
-                trace[traceLen++] = ((Uart.parityBits >>  0) & 0xff);
-                trace[traceLen++] = ((Uart.parityBits >>  8) & 0xff);
-                trace[traceLen++] = ((Uart.parityBits >> 16) & 0xff);
-                trace[traceLen++] = ((Uart.parityBits >> 24) & 0xff);
-                trace[traceLen++] = Uart.byteCnt;
-                memcpy(trace+traceLen, receivedCmd, Uart.byteCnt);
-                traceLen += Uart.byteCnt;
-                if(traceLen > TRACE_LENGTH) break;
-            }
-            /* And ready to receive another command. */
-            Uart.state = STATE_UNSYNCD;
-            /* And also reset the demod code, which might have been */
-            /* false-triggered by the commands from the reader. */
-            Demod.state = DEMOD_UNSYNCD;
-            LED_B_OFF();
-        }
+		int register readBufDataP = data - dmaBuf;
+		int register dmaBufDataP = DMA_BUFFER_SIZE - AT91C_BASE_PDC_SSC->PDC_RCR;
+		if (readBufDataP <= dmaBufDataP){
+			dataLen = dmaBufDataP - readBufDataP;
+		} else {
+			dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP;
+		}
+		// test for length of buffer
+		if(dataLen > maxDataLen) {
+			maxDataLen = dataLen;
+			if(dataLen > (9 * DMA_BUFFER_SIZE / 10)) {
+				Dbprintf("blew circular buffer! dataLen=%d", dataLen);
+				break;
+			}
+		}
+		if(dataLen < 1) continue;
 
-        if(ManchesterDecoding(smpl & 0x0F)) {
-            rsamples = samples - Demod.samples;
-            LED_B_ON();
-
-            // timestamp, as a count of samples
-            trace[traceLen++] = ((rsamples >>  0) & 0xff);
-            trace[traceLen++] = ((rsamples >>  8) & 0xff);
-            trace[traceLen++] = ((rsamples >> 16) & 0xff);
-            trace[traceLen++] = 0x80 | ((rsamples >> 24) & 0xff);
-            trace[traceLen++] = ((Demod.parityBits >>  0) & 0xff);
-            trace[traceLen++] = ((Demod.parityBits >>  8) & 0xff);
-            trace[traceLen++] = ((Demod.parityBits >> 16) & 0xff);
-            trace[traceLen++] = ((Demod.parityBits >> 24) & 0xff);
-            // length
-            trace[traceLen++] = Demod.len;
-            memcpy(trace+traceLen, receivedResponse, Demod.len);
-            traceLen += Demod.len;
-            if(traceLen > TRACE_LENGTH) break;
-
-            triggered = TRUE;
-
-            // And ready to receive another response.
-            memset(&Demod, 0, sizeof(Demod));
-            Demod.output = receivedResponse;
-            Demod.state = DEMOD_UNSYNCD;
-            LED_C_OFF();
-        }
+		// primary buffer was stopped( <-- we lost data!
+		if (!AT91C_BASE_PDC_SSC->PDC_RCR) {
+			AT91C_BASE_PDC_SSC->PDC_RPR = (uint32_t) dmaBuf;
+			AT91C_BASE_PDC_SSC->PDC_RCR = DMA_BUFFER_SIZE;
+			Dbprintf("RxEmpty ERROR!!! data length:%d", dataLen); // temporary
+		}
+		// secondary buffer sets as primary, secondary buffer was stopped
+		if (!AT91C_BASE_PDC_SSC->PDC_RNCR) {
+			AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf;
+			AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
+		}
 
-        if(BUTTON_PRESS()) {
-            DbpString("cancelled_a");
-            goto done;
-        }
-    }
+		LED_A_OFF();
+		
+		if (rsamples & 0x01) {				// Need two samples to feed Miller and Manchester-Decoder
+
+			if(!TagIsActive) {		// no need to try decoding reader data if the tag is sending
+				uint8_t readerdata = (previous_data & 0xF0) | (*data >> 4);
+				if (MillerDecoding(readerdata, (rsamples-1)*4)) {
+					LED_C_ON();
+
+					// check - if there is a short 7bit request from reader
+					if ((!triggered) && (param & 0x02) && (Uart.len == 1) && (Uart.bitCount == 7)) triggered = TRUE;
+
+					if(triggered) {
+						if (!LogTrace(receivedCmd, 
+										Uart.len, 
+										Uart.startTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER,
+										Uart.endTime*16 - DELAY_READER_AIR2ARM_AS_SNIFFER,
+										Uart.parity, 
+										TRUE)) break;
+					}
+					/* And ready to receive another command. */
+					UartReset();
+					/* And also reset the demod code, which might have been */
+					/* false-triggered by the commands from the reader. */
+					DemodReset();
+					LED_B_OFF();
+				}
+				ReaderIsActive = (Uart.state != STATE_UNSYNCD);
+			}
 
-    DbpString("COMMAND FINISHED");
+			if(!ReaderIsActive) {		// no need to try decoding tag data if the reader is sending - and we cannot afford the time
+				uint8_t tagdata = (previous_data << 4) | (*data & 0x0F);
+				if(ManchesterDecoding(tagdata, 0, (rsamples-1)*4)) {
+					LED_B_ON();
 
-    Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
-    Dbprintf("%x %x %x", Uart.byteCntMax, traceLen, (int)Uart.output[0]);
+					if (!LogTrace(receivedResponse, 
+									Demod.len, 
+									Demod.startTime*16 - DELAY_TAG_AIR2ARM_AS_SNIFFER, 
+									Demod.endTime*16 - DELAY_TAG_AIR2ARM_AS_SNIFFER,
+									Demod.parity,
+									FALSE)) break;
 
-done:
-    AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
-    Dbprintf("%x %x %x", maxBehindBy, Uart.state, Uart.byteCnt);
-    Dbprintf("%x %x %x", Uart.byteCntMax, traceLen, (int)Uart.output[0]);
-    LED_A_OFF();
-    LED_B_OFF();
-	LED_C_OFF();
-	LED_D_OFF();
+					if ((!triggered) && (param & 0x01)) triggered = TRUE;
+
+					// And ready to receive another response.
+					DemodReset();
+					// And reset the Miller decoder including itS (now outdated) input buffer
+					UartInit(receivedCmd, receivedCmdPar);
+					LED_C_OFF();
+				} 
+				TagIsActive = (Demod.state != DEMOD_UNSYNCD);
+			}
+		}
+
+		previous_data = *data;
+		rsamples++;
+		data++;
+		if(data == dmaBuf + DMA_BUFFER_SIZE) {
+			data = dmaBuf;
+		}
+	} // main cycle
+
+	if (MF_DBGLEVEL >= 1) {
+		Dbprintf("maxDataLen=%d, Uart.state=%x, Uart.len=%d", maxDataLen, Uart.state, Uart.len);
+		Dbprintf("traceLen=%d, Uart.output[0]=%08x", BigBuf_get_traceLen(), (uint32_t)Uart.output[0]);
+	}
+	FpgaDisableSscDma();
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+	LEDsoff();
+	set_tracing(FALSE);	
 }
 
 //-----------------------------------------------------------------------------
 // Prepare tag messages
 //-----------------------------------------------------------------------------
-static void CodeIso14443aAsTagPar(const uint8_t *cmd, int len, uint32_t dwParity)
-{
-	int i;
-//	int oddparity;
-
+static void CodeIso14443aAsTagPar(const uint8_t *cmd, uint16_t len, uint8_t *parity) {
 	ToSendReset();
 
 	// Correction bit, might be removed when not needed
@@ -803,15 +680,13 @@ static void CodeIso14443aAsTagPar(const uint8_t *cmd, int len, uint32_t dwParity
 	
 	// Send startbit
 	ToSend[++ToSendMax] = SEC_D;
+	LastProxToAirDuration = 8 * ToSendMax - 4;
 
-	for(i = 0; i < len; i++) {
-		int j;
+	for(uint16_t i = 0; i < len; i++) {
 		uint8_t b = cmd[i];
 
 		// Data bits
-//		oddparity = 0x01;
-		for(j = 0; j < 8; j++) {
-//			oddparity ^= (b & 1);
+		for(uint16_t j = 0; j < 8; j++) {
 			if(b & 1) {
 				ToSend[++ToSendMax] = SEC_D;
 			} else {
@@ -820,52 +695,33 @@ static void CodeIso14443aAsTagPar(const uint8_t *cmd, int len, uint32_t dwParity
 			b >>= 1;
 		}
 
-	// Get the parity bit
-		if ((dwParity >> i) & 0x01) {
+		// Get the parity bit
+		if (parity[i>>3] & (0x80>>(i&0x0007))) {
 			ToSend[++ToSendMax] = SEC_D;
+			LastProxToAirDuration = 8 * ToSendMax - 4;
 		} else {
 			ToSend[++ToSendMax] = SEC_E;
+			LastProxToAirDuration = 8 * ToSendMax;
 		}
-		
-			// Parity bit
-//			if(oddparity) {
-//				ToSend[++ToSendMax] = SEC_D;
-//			} else {
-//				ToSend[++ToSendMax] = SEC_E;
-//			}
-
-//		if (oddparity != ((dwParity >> i) & 0x01))
-//		  Dbprintf("par error. i=%d", i);
 	}
 
 	// Send stopbit
 	ToSend[++ToSendMax] = SEC_F;
 
-	// Flush the buffer in FPGA!!
-	for(i = 0; i < 5; i++) {
-//		ToSend[++ToSendMax] = SEC_F;
-	}
-
 	// Convert from last byte pos to length
-	ToSendMax++;
-
-    // Add a few more for slop
-//    ToSend[ToSendMax++] = 0x00;
-//	ToSend[ToSendMax++] = 0x00;
+	++ToSendMax;
 }
 
-static void CodeIso14443aAsTag(const uint8_t *cmd, int len){
-	CodeIso14443aAsTagPar(cmd, len, GetParity(cmd, len));
+static void CodeIso14443aAsTag(const uint8_t *cmd, uint16_t len) {
+	uint8_t par[MAX_PARITY_SIZE] = {0};
+	GetParity(cmd, len, par);
+	CodeIso14443aAsTagPar(cmd, len, par);
 }
 
-//-----------------------------------------------------------------------------
-// This is to send a NACK kind of answer, its only 3 bits, I know it should be 4
-//-----------------------------------------------------------------------------
-static void CodeStrangeAnswerAsTag()
-{
-	int i;
+static void Code4bitAnswerAsTag(uint8_t cmd) {
+	uint8_t b = cmd;
 
-    ToSendReset();
+	ToSendReset();
 
 	// Correction bit, might be removed when not needed
 	ToSendStuffBit(0);
@@ -880,66 +736,22 @@ static void CodeStrangeAnswerAsTag()
 	// Send startbit
 	ToSend[++ToSendMax] = SEC_D;
 
-	// 0
-	ToSend[++ToSendMax] = SEC_E;
-
-	// 0
-	ToSend[++ToSendMax] = SEC_E;
-
-	// 1
-	ToSend[++ToSendMax] = SEC_D;
+	for(uint8_t i = 0; i < 4; i++) {
+		if(b & 1) {
+			ToSend[++ToSendMax] = SEC_D;
+			LastProxToAirDuration = 8 * ToSendMax - 4;
+		} else {
+			ToSend[++ToSendMax] = SEC_E;
+			LastProxToAirDuration = 8 * ToSendMax;
+		}
+		b >>= 1;
+	}
 
-    // Send stopbit
+	// Send stopbit
 	ToSend[++ToSendMax] = SEC_F;
 
-	// Flush the buffer in FPGA!!
-	for(i = 0; i < 5; i++) {
-		ToSend[++ToSendMax] = SEC_F;
-	}
-
-    // Convert from last byte pos to length
-    ToSendMax++;
-}
-
-static void Code4bitAnswerAsTag(uint8_t cmd)
-{
-	int i;
-
-    ToSendReset();
-
-	// Correction bit, might be removed when not needed
-	ToSendStuffBit(0);
-	ToSendStuffBit(0);
-	ToSendStuffBit(0);
-	ToSendStuffBit(0);
-	ToSendStuffBit(1);  // 1
-	ToSendStuffBit(0);
-	ToSendStuffBit(0);
-	ToSendStuffBit(0);
-
-	// Send startbit
-	ToSend[++ToSendMax] = SEC_D;
-
-	uint8_t b = cmd;
-	for(i = 0; i < 4; i++) {
-		if(b & 1) {
-			ToSend[++ToSendMax] = SEC_D;
-		} else {
-			ToSend[++ToSendMax] = SEC_E;
-		}
-		b >>= 1;
-	}
-
-	// Send stopbit
-	ToSend[++ToSendMax] = SEC_F;
-
-	// Flush the buffer in FPGA!!
-	for(i = 0; i < 5; i++) {
-		ToSend[++ToSendMax] = SEC_F;
-	}
-
-    // Convert from last byte pos to length
-    ToSendMax++;
+	// Convert from last byte pos to length
+	ToSendMax++;
 }
 
 //-----------------------------------------------------------------------------
@@ -947,265 +759,564 @@ static void Code4bitAnswerAsTag(uint8_t cmd)
 // Stop when button is pressed
 // Or return TRUE when command is captured
 //-----------------------------------------------------------------------------
-static int GetIso14443aCommandFromReader(uint8_t *received, int *len, int maxLen)
-{
+static int GetIso14443aCommandFromReader(uint8_t *received, uint8_t *parity, int *len) {
     // Set FPGA mode to "simulated ISO 14443 tag", no modulation (listen
     // only, since we are receiving, not transmitting).
     // Signal field is off with the appropriate LED
     LED_D_OFF();
     FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
 
-    // Now run a `software UART' on the stream of incoming samples.
-    Uart.output = received;
-    Uart.byteCntMax = maxLen;
-    Uart.state = STATE_UNSYNCD;
+    // Now run a `software UART` on the stream of incoming samples.
+	UartInit(received, parity);
+
+	// clear RXRDY:
+    uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
 
     for(;;) {
         WDT_HIT();
 
         if(BUTTON_PRESS()) return FALSE;
-
-        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-            AT91C_BASE_SSC->SSC_THR = 0x00;
-        }
+		
         if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-            uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-			if(MillerDecoding((b & 0xf0) >> 4)) {
-				*len = Uart.byteCnt;
+            b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+			if(MillerDecoding(b, 0)) {
+				*len = Uart.len;
 				return TRUE;
 			}
-			if(MillerDecoding(b & 0x0f)) {
-				*len = Uart.byteCnt;
-				return TRUE;
-			}
-        }
+ 		}
     }
 }
-static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded);
-
-//-----------------------------------------------------------------------------
-// Main loop of simulated tag: receive commands from reader, decide what
-// response to send, and send it.
-//-----------------------------------------------------------------------------
-void SimulateIso14443aTag(int tagType, int TagUid)
-{
-	// This function contains the tag emulation
-
-	// Prepare protocol messages
-    // static const uint8_t cmd1[] = { 0x26 };
-//     static const uint8_t response1[] = { 0x02, 0x00 }; // Says: I am Mifare 4k - original line - greg
-//
-	static const uint8_t response1[] = { 0x44, 0x03 }; // Says: I am a DESFire Tag, ph33r me
-//	static const uint8_t response1[] = { 0x44, 0x00 }; // Says: I am a ULTRALITE Tag, 0wn me
-
-	// UID response
-    // static const uint8_t cmd2[] = { 0x93, 0x20 };
-    //static const uint8_t response2[] = { 0x9a, 0xe5, 0xe4, 0x43, 0xd8 }; // original value - greg
 
-// my desfire
-    static const uint8_t response2[] = { 0x88, 0x04, 0x21, 0x3f, 0x4d }; // known uid - note cascade (0x88), 2nd byte (0x04) = NXP/Phillips
-
-
-// When reader selects us during cascade1 it will send cmd3
-//uint8_t response3[] = { 0x04, 0x00, 0x00 }; // SAK Select (cascade1) successful response (ULTRALITE)
-uint8_t response3[] = { 0x24, 0x00, 0x00 }; // SAK Select (cascade1) successful response (DESFire)
-ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]);
-
-// send cascade2 2nd half of UID
-static const uint8_t response2a[] = { 0x51, 0x48, 0x1d, 0x80, 0x84 }; //  uid - cascade2 - 2nd half (4 bytes) of UID+ BCCheck
-// NOTE : THE CRC on the above may be wrong as I have obfuscated the actual UID
-
-// When reader selects us during cascade2 it will send cmd3a
-//uint8_t response3a[] = { 0x00, 0x00, 0x00 }; // SAK Select (cascade2) successful response (ULTRALITE)
-uint8_t response3a[] = { 0x20, 0x00, 0x00 }; // SAK Select (cascade2) successful response (DESFire)
-ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]);
-
-    static const uint8_t response5[] = { 0x00, 0x00, 0x00, 0x00 }; // Very random tag nonce
-
-    uint8_t *resp;
-    int respLen;
-
-    // Longest possible response will be 16 bytes + 2 CRC = 18 bytes
-	// This will need
+bool prepare_tag_modulation(tag_response_info_t* response_info, size_t max_buffer_size) {
+	// Example response, answer to MIFARE Classic read block will be 16 bytes + 2 CRC = 18 bytes
+	// This will need the following byte array for a modulation sequence
 	//    144        data bits (18 * 8)
 	//     18        parity bits
 	//      2        Start and stop
 	//      1        Correction bit (Answer in 1172 or 1236 periods, see FPGA)
 	//      1        just for the case
 	// ----------- +
-	//    166
-	//
-	// 166 bytes, since every bit that needs to be send costs us a byte
+	//    166 bytes, since every bit that needs to be send costs us a byte
 	//
+	// Prepare the tag modulation bits from the message
+	CodeIso14443aAsTag(response_info->response,response_info->response_n);
 
-    // Respond with card type
-    uint8_t *resp1 = (((uint8_t *)BigBuf) + 800);
-    int resp1Len;
-
-    // Anticollision cascade1 - respond with uid
-    uint8_t *resp2 = (((uint8_t *)BigBuf) + 970);
-    int resp2Len;
-
-    // Anticollision cascade2 - respond with 2nd half of uid if asked
-    // we're only going to be asked if we set the 1st byte of the UID (during cascade1) to 0x88
-    uint8_t *resp2a = (((uint8_t *)BigBuf) + 1140);
-    int resp2aLen;
-
-    // Acknowledge select - cascade 1
-    uint8_t *resp3 = (((uint8_t *)BigBuf) + 1310);
-    int resp3Len;
-
-    // Acknowledge select - cascade 2
-    uint8_t *resp3a = (((uint8_t *)BigBuf) + 1480);
-    int resp3aLen;
+	// Make sure we do not exceed the free buffer space
+	if (ToSendMax > max_buffer_size) {
+		Dbprintf("Out of memory, when modulating bits for tag answer:");
+		Dbhexdump(response_info->response_n,response_info->response,false);
+		return FALSE;
+	}
 
-    // Response to a read request - not implemented atm
-    uint8_t *resp4 = (((uint8_t *)BigBuf) + 1550);
-    int resp4Len;
+	// Copy the byte array, used for this modulation to the buffer position
+	memcpy(response_info->modulation,ToSend,ToSendMax);
 
-    // Authenticate response - nonce
-    uint8_t *resp5 = (((uint8_t *)BigBuf) + 1720);
-    int resp5Len;
+	// Store the number of bytes that were used for encoding/modulation and the time needed to transfer them
+	response_info->modulation_n = ToSendMax;
+	response_info->ProxToAirDuration = LastProxToAirDuration;
+	return TRUE;
+}
 
-    uint8_t *receivedCmd = (uint8_t *)BigBuf;
-    int len;
+// "precompile" responses. There are 7 predefined responses with a total of 28 bytes data to transmit.
+// Coded responses need one byte per bit to transfer (data, parity, start, stop, correction) 
+// 28 * 8 data bits, 28 * 1 parity bits, 7 start bits, 7 stop bits, 7 correction bits
+// -> need 273 bytes buffer
+// 44 * 8 data bits, 44 * 1 parity bits, 9 start bits, 9 stop bits, 9 correction bits --370
+// 47 * 8 data bits, 47 * 1 parity bits, 10 start bits, 10 stop bits, 10 correction bits 
+#define ALLOCATED_TAG_MODULATION_BUFFER_SIZE 453 
+
+bool prepare_allocated_tag_modulation(tag_response_info_t* response_info) {
+	// Retrieve and store the current buffer index
+	response_info->modulation = free_buffer_pointer;
+
+	// Determine the maximum size we can use from our buffer
+	size_t max_buffer_size = ALLOCATED_TAG_MODULATION_BUFFER_SIZE;
+
+	// Forward the prepare tag modulation function to the inner function
+	if (prepare_tag_modulation(response_info, max_buffer_size)) {
+		// Update the free buffer offset
+		free_buffer_pointer += ToSendMax;
+		return true;
+	} else {
+		return false;
+	}
+}
 
-    int i;
-	int u;
-	uint8_t b;
+//-----------------------------------------------------------------------------
+// Main loop of simulated tag: receive commands from reader, decide what
+// response to send, and send it.
+// 'hf 14a sim'
+//-----------------------------------------------------------------------------
+void SimulateIso14443aTag(int tagType, int flags, byte_t* data) {
 
-	// To control where we are in the protocol
-	int order = 0;
-	int lastorder;
+	uint8_t sak = 0;
+	uint32_t cuid = 0;			
+	uint32_t nonce = 0;
+	
+	// PACK response to PWD AUTH for EV1/NTAG
+	uint8_t response8[4] = {0,0,0,0};
+	// Counter for EV1/NTAG
+	uint32_t counters[] = {0,0,0};
+	
+	// The first response contains the ATQA (note: bytes are transmitted in reverse order).
+	uint8_t response1[] = {0,0};
 
-	// Just to allow some checks
-	int happened = 0;
-	int happened2 = 0;
+	// Here, we collect CUID, block1, keytype1, NT1, NR1, AR1, CUID, block2, keytyp2, NT2, NR2, AR2
+	// it should also collect block, keytype.
+	uint8_t cardAUTHSC = 0;
+	uint8_t cardAUTHKEY = 0xff;  // no authentication
+	// allow collecting up to 8 sets of nonces to allow recovery of up to 8 keys
+	#define ATTACK_KEY_COUNT 8 // keep same as define in cmdhfmf.c -> readerAttack()
+	nonces_t ar_nr_resp[ATTACK_KEY_COUNT*2]; // for 2 separate attack types (nml, moebius)
+	memset(ar_nr_resp, 0x00, sizeof(ar_nr_resp));
+
+	uint8_t ar_nr_collected[ATTACK_KEY_COUNT*2]; // for 2nd attack type (moebius)
+	memset(ar_nr_collected, 0x00, sizeof(ar_nr_collected));
+	uint8_t	nonce1_count = 0;
+	uint8_t	nonce2_count = 0;
+	uint8_t	moebius_n_count = 0;
+	bool gettingMoebius = false;
+	uint8_t	mM = 0; // moebius_modifier for collection storage
 
-    int cmdsRecvd = 0;
+	
+	switch (tagType) {
+		case 1: { // MIFARE Classic 1k 
+			response1[0] = 0x04;
+			sak = 0x08;
+		} break;
+		case 2: { // MIFARE Ultralight
+			response1[0] = 0x44;
+			sak = 0x00;
+		} break;
+		case 3: { // MIFARE DESFire
+			response1[0] = 0x04;
+			response1[1] = 0x03;
+			sak = 0x20;
+		} break;
+		case 4: { // ISO/IEC 14443-4 - javacard (JCOP)
+			response1[0] = 0x04;
+			sak = 0x28;
+		} break;
+		case 5: { // MIFARE TNP3XXX
+			response1[0] = 0x01;
+			response1[1] = 0x0f;
+			sak = 0x01;
+		} break;
+		case 6: { // MIFARE Mini 320b
+			response1[0] = 0x44;
+			sak = 0x09;
+		} break;
+		case 7: { // NTAG
+			response1[0] = 0x44;
+			sak = 0x00;
+			// PACK
+			response8[0] = 0x80;
+			response8[1] = 0x80;
+			ComputeCrc14443(CRC_14443_A, response8, 2, &response8[2], &response8[3]);
+			// uid not supplied then get from emulator memory
+			if (data[0]==0) {
+				uint16_t start = 4 * (0+12);  
+				uint8_t emdata[8];
+				emlGetMemBt( emdata, start, sizeof(emdata));
+				memcpy(data, emdata, 3); // uid bytes 0-2
+				memcpy(data+3, emdata+4, 4); // uid bytes 3-7
+				flags |= FLAG_7B_UID_IN_DATA;
+			}
+		} break;		
+		default: {
+			Dbprintf("Error: unkown tagtype (%d)",tagType);
+			return;
+		} break;
+	}
+	
+	// The second response contains the (mandatory) first 24 bits of the UID
+	uint8_t response2[5] = {0x00};
 
-	int fdt_indicator;
+	// For UID size 7, 
+	uint8_t response2a[5] = {0x00};
+	
+	if ( (flags & FLAG_7B_UID_IN_DATA) == FLAG_7B_UID_IN_DATA ) {
+		response2[0] = 0x88;  // Cascade Tag marker
+		response2[1] = data[0];
+		response2[2] = data[1];
+		response2[3] = data[2];
+
+		response2a[0] = data[3];
+		response2a[1] = data[4];
+		response2a[2] = data[5];
+		response2a[3] = data[6]; //??
+		response2a[4] = response2a[0] ^ response2a[1] ^ response2a[2] ^ response2a[3];
+
+		// Configure the ATQA and SAK accordingly
+		response1[0] |= 0x40;
+		sak |= 0x04;
+		
+		cuid = bytes_to_num(data+3, 4);
+	} else {
+		memcpy(response2, data, 4);
+		// Configure the ATQA and SAK accordingly
+		response1[0] &= 0xBF;
+		sak &= 0xFB;
+		cuid = bytes_to_num(data, 4);
+	}
 
-    memset(receivedCmd, 0x44, 400);
+	// Calculate the BitCountCheck (BCC) for the first 4 bytes of the UID.
+	response2[4] = response2[0] ^ response2[1] ^ response2[2] ^ response2[3];
 
-	// Prepare the responses of the anticollision phase
-	// there will be not enough time to do this at the moment the reader sends it REQA
+	// Prepare the mandatory SAK (for 4 and 7 byte UID)
+	uint8_t response3[3]  = {sak, 0x00, 0x00};
+	ComputeCrc14443(CRC_14443_A, response3, 1, &response3[1], &response3[2]);
 
-	// Answer to request
-	CodeIso14443aAsTag(response1, sizeof(response1));
-    memcpy(resp1, ToSend, ToSendMax); resp1Len = ToSendMax;
+	// Prepare the optional second SAK (for 7 byte UID), drop the cascade bit
+	uint8_t response3a[3]  = {0x00};
+	response3a[0] = sak & 0xFB;
+	ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]);
 
-	// Send our UID (cascade 1)
-	CodeIso14443aAsTag(response2, sizeof(response2));
-    memcpy(resp2, ToSend, ToSendMax); resp2Len = ToSendMax;
+	uint8_t response5[] = { 0x01, 0x01, 0x01, 0x01 }; 				// Very random tag nonce
+	uint8_t response6[] = { 0x04, 0x58, 0x80, 0x02, 0x00, 0x00 }; 	// dummy ATS (pseudo-ATR), answer to RATS: 
+	// Format byte = 0x58: FSCI=0x08 (FSC=256), TA(1) and TC(1) present, 
+	// TA(1) = 0x80: different divisors not supported, DR = 1, DS = 1
+	// TB(1) = not present. Defaults: FWI = 4 (FWT = 256 * 16 * 2^4 * 1/fc = 4833us), SFGI = 0 (SFG = 256 * 16 * 2^0 * 1/fc = 302us)
+	// TC(1) = 0x02: CID supported, NAD not supported
+	ComputeCrc14443(CRC_14443_A, response6, 4, &response6[4], &response6[5]);
 
-	// Answer to select (cascade1)
-	CodeIso14443aAsTag(response3, sizeof(response3));
-    memcpy(resp3, ToSend, ToSendMax); resp3Len = ToSendMax;
+	// the randon nonce
+	nonce = bytes_to_num(response5, 4);	
+	
+	// Prepare GET_VERSION (different for UL EV-1 / NTAG)
+	// uint8_t response7_EV1[] = {0x00, 0x04, 0x03, 0x01, 0x01, 0x00, 0x0b, 0x03, 0xfd, 0xf7};  //EV1 48bytes VERSION.
+	// uint8_t response7_NTAG[] = {0x00, 0x04, 0x04, 0x02, 0x01, 0x00, 0x11, 0x03, 0x01, 0x9e}; //NTAG 215	
+	// Prepare CHK_TEARING
+	// uint8_t response9[] =  {0xBD,0x90,0x3f};
+	
+	#define TAG_RESPONSE_COUNT 10
+	tag_response_info_t responses[TAG_RESPONSE_COUNT] = {
+		{ .response = response1,  .response_n = sizeof(response1)  },  // Answer to request - respond with card type
+		{ .response = response2,  .response_n = sizeof(response2)  },  // Anticollision cascade1 - respond with uid
+		{ .response = response2a, .response_n = sizeof(response2a) },  // Anticollision cascade2 - respond with 2nd half of uid if asked
+		{ .response = response3,  .response_n = sizeof(response3)  },  // Acknowledge select - cascade 1
+		{ .response = response3a, .response_n = sizeof(response3a) },  // Acknowledge select - cascade 2
+		{ .response = response5,  .response_n = sizeof(response5)  },  // Authentication answer (random nonce)
+		{ .response = response6,  .response_n = sizeof(response6)  },  // dummy ATS (pseudo-ATR), answer to RATS
+
+		{ .response = response8,   .response_n = sizeof(response8) }  // EV1/NTAG PACK response
+	};	
+		// { .response = response7_NTAG, .response_n = sizeof(response7_NTAG)}, // EV1/NTAG GET_VERSION response
+		// { .response = response9,      .response_n = sizeof(response9)     }  // EV1/NTAG CHK_TEAR response
+	
 
-	// Send the cascade 2 2nd part of the uid
-	CodeIso14443aAsTag(response2a, sizeof(response2a));
-    memcpy(resp2a, ToSend, ToSendMax); resp2aLen = ToSendMax;
+	// Allocate 512 bytes for the dynamic modulation, created when the reader queries for it
+	// Such a response is less time critical, so we can prepare them on the fly
+	#define DYNAMIC_RESPONSE_BUFFER_SIZE 64
+	#define DYNAMIC_MODULATION_BUFFER_SIZE 512
+	uint8_t dynamic_response_buffer[DYNAMIC_RESPONSE_BUFFER_SIZE];
+	uint8_t dynamic_modulation_buffer[DYNAMIC_MODULATION_BUFFER_SIZE];
+	tag_response_info_t dynamic_response_info = {
+		.response = dynamic_response_buffer,
+		.response_n = 0,
+		.modulation = dynamic_modulation_buffer,
+		.modulation_n = 0
+	};
+  
+	// We need to listen to the high-frequency, peak-detected path.
+	iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
 
-	// Answer to select (cascade 2)
-	CodeIso14443aAsTag(response3a, sizeof(response3a));
-    memcpy(resp3a, ToSend, ToSendMax); resp3aLen = ToSendMax;
+	BigBuf_free_keep_EM();
+	clear_trace();
+	set_tracing(TRUE);
 
-	// Strange answer is an example of rare message size (3 bits)
-	CodeStrangeAnswerAsTag();
-	memcpy(resp4, ToSend, ToSendMax); resp4Len = ToSendMax;
+	// allocate buffers:
+	uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
+	uint8_t *receivedCmdPar = BigBuf_malloc(MAX_PARITY_SIZE);
+	free_buffer_pointer = BigBuf_malloc(ALLOCATED_TAG_MODULATION_BUFFER_SIZE);
 
-	// Authentication answer (random nonce)
-	CodeIso14443aAsTag(response5, sizeof(response5));
-    memcpy(resp5, ToSend, ToSendMax); resp5Len = ToSendMax;
+	// Prepare the responses of the anticollision phase
+	// there will be not enough time to do this at the moment the reader sends it REQA
+	for (size_t i=0; i<TAG_RESPONSE_COUNT; i++)
+		prepare_allocated_tag_modulation(&responses[i]);
 
-    // We need to listen to the high-frequency, peak-detected path.
-    SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-    FpgaSetupSsc();
+	int len = 0;
 
-    cmdsRecvd = 0;
+	// To control where we are in the protocol
+	int order = 0;
+	int lastorder;
 
-    LED_A_ON();
-	for(;;) {
+	// Just to allow some checks
+	int happened = 0;
+	int happened2 = 0;
+	int cmdsRecvd = 0;
+	tag_response_info_t* p_response;
 
-		if(!GetIso14443aCommandFromReader(receivedCmd, &len, 100)) {
-            DbpString("button press");
-            break;
-        }
-	// doob - added loads of debug strings so we can see what the reader is saying to us during the sim as hi14alist is not populated
-        // Okay, look at the command now.
-        lastorder = order;
-		i = 1; // first byte transmitted
-        if(receivedCmd[0] == 0x26) {
-			// Received a REQUEST
-			resp = resp1; respLen = resp1Len; order = 1;
-			//DbpString("Hello request from reader:");
-		} else if(receivedCmd[0] == 0x52) {
-			// Received a WAKEUP
-			resp = resp1; respLen = resp1Len; order = 6;
-//			//DbpString("Wakeup request from reader:");
-
-		} else if(receivedCmd[1] == 0x20 && receivedCmd[0] == 0x93) {	// greg - cascade 1 anti-collision
-			// Received request for UID (cascade 1)
-			resp = resp2; respLen = resp2Len; order = 2;
-//			DbpString("UID (cascade 1) request from reader:");
-//			DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);
-
-
-		} else if(receivedCmd[1] == 0x20 && receivedCmd[0] ==0x95) {	// greg - cascade 2 anti-collision
-			// Received request for UID (cascade 2)
-			resp = resp2a; respLen = resp2aLen; order = 20;
-//			DbpString("UID (cascade 2) request from reader:");
-//			DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);
-
-
-		} else if(receivedCmd[1] == 0x70 && receivedCmd[0] ==0x93) {	// greg - cascade 1 select
-			// Received a SELECT
-			resp = resp3; respLen = resp3Len; order = 3;
-//			DbpString("Select (cascade 1) request from reader:");
-//			DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);
-
-
-		} else if(receivedCmd[1] == 0x70 && receivedCmd[0] ==0x95) {	// greg - cascade 2 select
-			// Received a SELECT
-			resp = resp3a; respLen = resp3aLen; order = 30;
-//			DbpString("Select (cascade 2) request from reader:");
-//			DbpIntegers(receivedCmd[0], receivedCmd[1], receivedCmd[2]);
-
-
-		} else if(receivedCmd[0] == 0x30) {
-			// Received a READ
-			resp = resp4; respLen = resp4Len; order = 4; // Do nothing
-			Dbprintf("Read request from reader: %x %x %x",
-				receivedCmd[0], receivedCmd[1], receivedCmd[2]);
-
-
-		} else if(receivedCmd[0] == 0x50) {
-			// Received a HALT
-			resp = resp1; respLen = 0; order = 5; // Do nothing
-			DbpString("Reader requested we HALT!:");
-
-		} else if(receivedCmd[0] == 0x60) {
-			// Received an authentication request
-			resp = resp5; respLen = resp5Len; order = 7;
-			Dbprintf("Authenticate request from reader: %x %x %x",
-				receivedCmd[0], receivedCmd[1], receivedCmd[2]);
-
-		} else if(receivedCmd[0] == 0xE0) {
-			// Received a RATS request
-			resp = resp1; respLen = 0;order = 70;
-			Dbprintf("RATS request from reader: %x %x %x",
-				receivedCmd[0], receivedCmd[1], receivedCmd[2]);
-        } else {
-            // Never seen this command before
-		Dbprintf("Unknown command received from reader (len=%d): %x %x %x %x %x %x %x %x %x",
-			len,
-			receivedCmd[0], receivedCmd[1], receivedCmd[2],
-			receivedCmd[3], receivedCmd[4], receivedCmd[5],
-			receivedCmd[6], receivedCmd[7], receivedCmd[8]);
-			// Do not respond
-			resp = resp1; respLen = 0; order = 0;
-        }
+	LED_A_ON();
+	for(;;) {	
+		WDT_HIT();
+		
+		// Clean receive command buffer
+		if(!GetIso14443aCommandFromReader(receivedCmd, receivedCmdPar, &len)) {
+			DbpString("Button press");
+			break;
+		}
+		
+		// incease nonce at every command recieved
+		nonce++;
+		num_to_bytes(nonce, 4, response5);
+		
+		p_response = NULL;
+		
+		// Okay, look at the command now.
+		lastorder = order;
+		if(receivedCmd[0] == ISO14443A_CMD_REQA) { // Received a REQUEST
+			p_response = &responses[0]; order = 1;
+		} else if(receivedCmd[0] == ISO14443A_CMD_WUPA) { // Received a WAKEUP
+			p_response = &responses[0]; order = 6;
+		} else if(receivedCmd[1] == 0x20 && receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT) {	// Received request for UID (cascade 1)
+			p_response = &responses[1]; order = 2;
+		} else if(receivedCmd[1] == 0x20 && receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_2) { 	// Received request for UID (cascade 2)
+			p_response = &responses[2]; order = 20;
+		} else if(receivedCmd[1] == 0x70 && receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT) {	// Received a SELECT (cascade 1)
+			p_response = &responses[3]; order = 3;
+		} else if(receivedCmd[1] == 0x70 && receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_2) {	// Received a SELECT (cascade 2)
+			p_response = &responses[4]; order = 30;		
+		} else if(receivedCmd[0] == ISO14443A_CMD_READBLOCK) {	// Received a (plain) READ
+			uint8_t block = receivedCmd[1];
+			// if Ultralight or NTAG (4 byte blocks)
+			if ( tagType == 7 || tagType == 2 ) {
+				// first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
+				uint16_t start = 4 * (block+12);  
+				uint8_t emdata[MAX_MIFARE_FRAME_SIZE];
+				emlGetMemBt( emdata, start, 16);
+				AppendCrc14443a(emdata, 16);
+				EmSendCmdEx(emdata, sizeof(emdata), false);
+				// We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below
+				p_response = NULL;
+			} else { // all other tags (16 byte block tags)
+				uint8_t emdata[MAX_MIFARE_FRAME_SIZE];
+				emlGetMemBt( emdata, block, 16);
+				AppendCrc14443a(emdata, 16);
+				EmSendCmdEx(emdata, sizeof(emdata), false);
+				// EmSendCmdEx(data+(4*receivedCmd[1]),16,false);
+				// Dbprintf("Read request from reader: %x %x",receivedCmd[0],receivedCmd[1]);
+				// We already responded, do not send anything with the EmSendCmd14443aRaw() that is called below
+				p_response = NULL;
+			}
+		} else if(receivedCmd[0] == MIFARE_ULEV1_FASTREAD) {	// Received a FAST READ (ranged read)				
+			uint8_t emdata[MAX_FRAME_SIZE];
+			// first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
+			int start =  (receivedCmd[1]+12) * 4; 
+			int len   = (receivedCmd[2] - receivedCmd[1] + 1) * 4;
+			emlGetMemBt( emdata, start, len);
+			AppendCrc14443a(emdata, len);
+			EmSendCmdEx(emdata, len+2, false);				
+			p_response = NULL;		
+		} else if(receivedCmd[0] == MIFARE_ULEV1_READSIG && tagType == 7) {	// Received a READ SIGNATURE -- 
+			// first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
+			uint16_t start = 4 * 4;
+			uint8_t emdata[34];
+			emlGetMemBt( emdata, start, 32);
+			AppendCrc14443a(emdata, 32);
+			EmSendCmdEx(emdata, sizeof(emdata), false);
+			p_response = NULL;					
+		} else if (receivedCmd[0] == MIFARE_ULEV1_READ_CNT && tagType == 7) {	// Received a READ COUNTER -- 
+			uint8_t index = receivedCmd[1];
+			uint8_t data[] =  {0x00,0x00,0x00,0x14,0xa5};
+			if ( counters[index] > 0) {
+				num_to_bytes(counters[index], 3, data);
+				AppendCrc14443a(data, sizeof(data)-2);
+			}
+			EmSendCmdEx(data,sizeof(data),false);				
+			p_response = NULL;
+		} else if (receivedCmd[0] == MIFARE_ULEV1_INCR_CNT && tagType == 7) {	// Received a INC COUNTER -- 
+			// number of counter
+			uint8_t counter = receivedCmd[1];
+			uint32_t val = bytes_to_num(receivedCmd+2,4);
+			counters[counter] = val;
+		
+			// send ACK
+			uint8_t ack[] = {0x0a};
+			EmSendCmdEx(ack,sizeof(ack),false);
+			p_response = NULL;			
+		} else if(receivedCmd[0] == MIFARE_ULEV1_CHECKTEAR && tagType == 7) {	// Received a CHECK_TEARING_EVENT -- 
+			// first 12 blocks of emu are [getversion answer - check tearing - pack - 0x00 - signature]
+			uint8_t emdata[3];
+			uint8_t counter=0;
+			if (receivedCmd[1]<3) counter = receivedCmd[1];
+			emlGetMemBt( emdata, 10+counter, 1);
+			AppendCrc14443a(emdata, sizeof(emdata)-2);
+			EmSendCmdEx(emdata, sizeof(emdata), false);	
+			p_response = NULL;		
+		} else if(receivedCmd[0] == ISO14443A_CMD_HALT) {	// Received a HALT
+			LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+			p_response = NULL;
+		} else if(receivedCmd[0] == MIFARE_AUTH_KEYA || receivedCmd[0] == MIFARE_AUTH_KEYB) {	// Received an authentication request				
+			if ( tagType == 7 ) {   // IF NTAG /EV1  0x60 == GET_VERSION, not a authentication request.
+				uint8_t emdata[10];
+				emlGetMemBt( emdata, 0, 8 );
+				AppendCrc14443a(emdata, sizeof(emdata)-2);
+				EmSendCmdEx(emdata, sizeof(emdata), false);
+				p_response = NULL;
+			} else {
+				cardAUTHSC = receivedCmd[1] / 4; // received block num
+				cardAUTHKEY = receivedCmd[0] - 0x60;
+				p_response = &responses[5]; order = 7;
+			}
+		} else if(receivedCmd[0] == ISO14443A_CMD_RATS) {	// Received a RATS request
+			if (tagType == 1 || tagType == 2) {	// RATS not supported
+				EmSend4bit(CARD_NACK_NA);
+				p_response = NULL;
+			} else {
+				p_response = &responses[6]; order = 70;
+			}
+		} else if (order == 7 && len == 8) { // Received {nr] and {ar} (part of authentication)
+			LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+			uint32_t nr = bytes_to_num(receivedCmd,4);
+			uint32_t ar = bytes_to_num(receivedCmd+4,4);
+
+			// Collect AR/NR per keytype & sector
+			if ( (flags & FLAG_NR_AR_ATTACK) == FLAG_NR_AR_ATTACK ) {
+					for (uint8_t i = 0; i < ATTACK_KEY_COUNT; i++) {
+						if ( ar_nr_collected[i+mM]==0 || ((cardAUTHSC == ar_nr_resp[i+mM].sector) && (cardAUTHKEY == ar_nr_resp[i+mM].keytype) && (ar_nr_collected[i+mM] > 0)) ) {
+							// if first auth for sector, or matches sector and keytype of previous auth
+							if (ar_nr_collected[i+mM] < 2) {
+								// if we haven't already collected 2 nonces for this sector
+								if (ar_nr_resp[ar_nr_collected[i+mM]].ar != ar) {
+									// Avoid duplicates... probably not necessary, ar should vary. 
+									if (ar_nr_collected[i+mM]==0) {
+										// first nonce collect
+										ar_nr_resp[i+mM].cuid = cuid;
+										ar_nr_resp[i+mM].sector = cardAUTHSC;
+										ar_nr_resp[i+mM].keytype = cardAUTHKEY;
+										ar_nr_resp[i+mM].nonce = nonce;
+										ar_nr_resp[i+mM].nr = nr;
+										ar_nr_resp[i+mM].ar = ar;
+										nonce1_count++;
+										// add this nonce to first moebius nonce
+										ar_nr_resp[i+ATTACK_KEY_COUNT].cuid = cuid;
+										ar_nr_resp[i+ATTACK_KEY_COUNT].sector = cardAUTHSC;
+										ar_nr_resp[i+ATTACK_KEY_COUNT].keytype = cardAUTHKEY;
+										ar_nr_resp[i+ATTACK_KEY_COUNT].nonce = nonce;
+										ar_nr_resp[i+ATTACK_KEY_COUNT].nr = nr;
+										ar_nr_resp[i+ATTACK_KEY_COUNT].ar = ar;
+										ar_nr_collected[i+ATTACK_KEY_COUNT]++;
+									} else { // second nonce collect (std and moebius)
+										ar_nr_resp[i+mM].nonce2 = nonce;
+										ar_nr_resp[i+mM].nr2 = nr;
+										ar_nr_resp[i+mM].ar2 = ar;
+										if (!gettingMoebius) {
+											nonce2_count++;
+											// check if this was the last second nonce we need for std attack
+											if ( nonce2_count == nonce1_count ) {
+												// done collecting std test switch to moebius
+												// first finish incrementing last sample
+												ar_nr_collected[i+mM]++; 
+												// switch to moebius collection
+												gettingMoebius = true;
+												mM = ATTACK_KEY_COUNT;
+												break;
+											}
+										} else {
+											moebius_n_count++;
+											// if we've collected all the nonces we need - finish.
+											if (nonce1_count == moebius_n_count) {
+												cmd_send(CMD_ACK,CMD_SIMULATE_MIFARE_CARD,0,0,&ar_nr_resp,sizeof(ar_nr_resp));
+												nonce1_count = 0;
+												nonce2_count = 0;
+												moebius_n_count = 0;
+												gettingMoebius = false;
+											}
+										}
+									}
+									ar_nr_collected[i+mM]++;
+								}
+							}
+							// we found right spot for this nonce stop looking
+							break;
+						}
+					}
+				}
+			
+		} else if (receivedCmd[0] == MIFARE_ULC_AUTH_1 ) { // ULC authentication, or Desfire Authentication
+		} else if (receivedCmd[0] == MIFARE_ULEV1_AUTH) { // NTAG / EV-1 authentication
+			if ( tagType == 7 ) {
+				uint16_t start = 13; // first 4 blocks of emu are [getversion answer - check tearing - pack - 0x00]
+				uint8_t emdata[4];
+				emlGetMemBt( emdata, start, 2);
+				AppendCrc14443a(emdata, 2);
+				EmSendCmdEx(emdata, sizeof(emdata), false);
+				p_response = NULL;
+				uint32_t pwd = bytes_to_num(receivedCmd+1,4);
+				
+				if ( MF_DBGLEVEL >= 3) Dbprintf("Auth attempt: %08x", pwd);	
+			}
+		} else {
+			// Check for ISO 14443A-4 compliant commands, look at left nibble
+			switch (receivedCmd[0]) {
+				case 0x02:
+				case 0x03: {  // IBlock (command no CID)
+					dynamic_response_info.response[0] = receivedCmd[0];
+					dynamic_response_info.response[1] = 0x90;
+					dynamic_response_info.response[2] = 0x00;
+					dynamic_response_info.response_n = 3;
+				} break;
+				case 0x0B:
+				case 0x0A: { // IBlock (command CID)
+				  dynamic_response_info.response[0] = receivedCmd[0];
+				  dynamic_response_info.response[1] = 0x00;
+				  dynamic_response_info.response[2] = 0x90;
+				  dynamic_response_info.response[3] = 0x00;
+				  dynamic_response_info.response_n = 4;
+				} break;
+
+				case 0x1A:
+				case 0x1B: { // Chaining command
+				  dynamic_response_info.response[0] = 0xaa | ((receivedCmd[0]) & 1);
+				  dynamic_response_info.response_n = 2;
+				} break;
+
+				case 0xaa:
+				case 0xbb: {
+				  dynamic_response_info.response[0] = receivedCmd[0] ^ 0x11;
+				  dynamic_response_info.response_n = 2;
+				} break;
+				  
+				case 0xBA: { // ping / pong
+					dynamic_response_info.response[0] = 0xAB;
+					dynamic_response_info.response[1] = 0x00;
+					dynamic_response_info.response_n = 2;
+				} break;
+
+				case 0xCA:
+				case 0xC2: { // Readers sends deselect command
+					dynamic_response_info.response[0] = 0xCA;
+					dynamic_response_info.response[1] = 0x00;
+					dynamic_response_info.response_n = 2;
+				} break;
+
+				default: {
+					// Never seen this command before
+					LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+					Dbprintf("Received unknown command (len=%d):",len);
+					Dbhexdump(len,receivedCmd,false);
+					// Do not respond
+					dynamic_response_info.response_n = 0;
+				} break;
+			}
+      
+			if (dynamic_response_info.response_n > 0) {
+				// Copy the CID from the reader query
+				dynamic_response_info.response[1] = receivedCmd[1];
+
+				// Add CRC bytes, always used in ISO 14443A-4 compliant cards
+				AppendCrc14443a(dynamic_response_info.response,dynamic_response_info.response_n);
+				dynamic_response_info.response_n += 2;
+        
+				if (prepare_tag_modulation(&dynamic_response_info,DYNAMIC_MODULATION_BUFFER_SIZE) == false) {
+					Dbprintf("Error preparing tag response");
+					LogTrace(receivedCmd, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+					break;
+				}
+				p_response = &dynamic_response_info;
+			}
+		}
 
 		// Count number of wakeups received after a halt
 		if(order == 6 && lastorder == 5) { happened++; }
@@ -1213,244 +1324,234 @@ ComputeCrc14443(CRC_14443_A, response3a, 1, &response3a[1], &response3a[2]);
 		// Count number of other messages after a halt
 		if(order != 6 && lastorder == 5) { happened2++; }
 
-		// Look at last parity bit to determine timing of answer
-		if((Uart.parityBits & 0x01) || receivedCmd[0] == 0x52) {
-			// 1236, so correction bit needed
-			i = 0;
+		// comment this limit if you want to simulation longer		
+		if (!tracing) {
+			Dbprintf("Trace Full. Simulation stopped.");
+			break;
 		}
-
-        memset(receivedCmd, 0x44, 32);
-
+		// comment this limit if you want to simulation longer
 		if(cmdsRecvd > 999) {
 			DbpString("1000 commands later...");
-            break;
-        }
-		else {
-			cmdsRecvd++;
+			break;
 		}
+		cmdsRecvd++;
 
-        if(respLen <= 0) continue;
-		//----------------------------
-		u = 0;
-		b = 0x00;
-		fdt_indicator = FALSE;
-
-		EmSendCmd14443aRaw(resp, respLen, receivedCmd[0] == 0x52);
-/*        // Modulate Manchester
-		FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_MOD);
-        AT91C_BASE_SSC->SSC_THR = 0x00;
-        FpgaSetupSsc();
-
-		// ### Transmit the response ###
-		u = 0;
-		b = 0x00;
-		fdt_indicator = FALSE;
-        for(;;) {
-            if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-				volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-                (void)b;
-            }
-            if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-				if(i > respLen) {
-					b = 0x00;
-					u++;
-				} else {
-					b = resp[i];
-					i++;
-				}
-				AT91C_BASE_SSC->SSC_THR = b;
-
-                if(u > 4) {
-                    break;
-                }
-            }
-			if(BUTTON_PRESS()) {
-			    break;
-			}
-        }
-*/
-    }
+		if (p_response != NULL) {
+			EmSendCmd14443aRaw(p_response->modulation, p_response->modulation_n, receivedCmd[0] == 0x52);
+			// do the tracing for the previous reader request and this tag answer:
+			uint8_t par[MAX_PARITY_SIZE] = {0x00};
+			GetParity(p_response->response, p_response->response_n, par);
+	
+			EmLogTrace(Uart.output, 
+						Uart.len, 
+						Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, 
+						Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 
+						Uart.parity,
+						p_response->response, 
+						p_response->response_n,
+						LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG,
+						(LastTimeProxToAirStart + p_response->ProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG, 
+						par);
+		}
+	}
 
-	Dbprintf("%x %x %x", happened, happened2, cmdsRecvd);
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+	set_tracing(FALSE);
+	BigBuf_free_keep_EM();
 	LED_A_OFF();
+	
+		if(flags & FLAG_NR_AR_ATTACK && MF_DBGLEVEL >= 1) {
+		for ( uint8_t	i = 0; i < ATTACK_KEY_COUNT; i++) {
+			if (ar_nr_collected[i] == 2) {
+				Dbprintf("Collected two pairs of AR/NR which can be used to extract %s from reader for sector %d:", (i<ATTACK_KEY_COUNT/2) ? "keyA" : "keyB", ar_nr_resp[i].sector);
+				Dbprintf("../tools/mfkey/mfkey32 %08x %08x %08x %08x %08x %08x",
+						ar_nr_resp[i].cuid,  //UID
+						ar_nr_resp[i].nonce, //NT
+						ar_nr_resp[i].nr,    //NR1
+						ar_nr_resp[i].ar,    //AR1
+						ar_nr_resp[i].nr2,   //NR2
+						ar_nr_resp[i].ar2    //AR2
+						);
+			}
+		}	
+		for ( uint8_t	i = ATTACK_KEY_COUNT; i < ATTACK_KEY_COUNT*2; i++) {
+			if (ar_nr_collected[i] == 2) {
+				Dbprintf("Collected two pairs of AR/NR which can be used to extract %s from reader for sector %d:", (i<ATTACK_KEY_COUNT/2) ? "keyA" : "keyB", ar_nr_resp[i].sector);
+				Dbprintf("../tools/mfkey/mfkey32v2 %08x %08x %08x %08x %08x %08x %08x",
+						ar_nr_resp[i].cuid,  //UID
+						ar_nr_resp[i].nonce, //NT
+						ar_nr_resp[i].nr,    //NR1
+						ar_nr_resp[i].ar,    //AR1
+						ar_nr_resp[i].nonce2,//NT2
+						ar_nr_resp[i].nr2,   //NR2
+						ar_nr_resp[i].ar2    //AR2
+						);
+			}
+		}
+	}
+	
+	if (MF_DBGLEVEL >= 4){
+		Dbprintf("-[ Wake ups after halt [%d]", happened);
+		Dbprintf("-[ Messages after halt [%d]", happened2);
+		Dbprintf("-[ Num of received cmd [%d]", cmdsRecvd);
+	}
 }
 
-//-----------------------------------------------------------------------------
+// prepare a delayed transfer. This simply shifts ToSend[] by a number
+// of bits specified in the delay parameter.
+void PrepareDelayedTransfer(uint16_t delay) {
+	delay &= 0x07;
+	if (!delay) return;
+
+	uint8_t bitmask = 0;
+	uint8_t bits_to_shift = 0;
+	uint8_t bits_shifted = 0;
+	uint16_t i = 0;
+
+	for (i = 0; i < delay; ++i)
+		bitmask |= (0x01 << i);
+
+	ToSend[++ToSendMax] = 0x00;
+
+	for (i = 0; i < ToSendMax; ++i) {
+			bits_to_shift = ToSend[i] & bitmask;
+			ToSend[i] = ToSend[i] >> delay;
+			ToSend[i] = ToSend[i] | (bits_shifted << (8 - delay));
+			bits_shifted = bits_to_shift;
+		}
+	}
+
+
+//-------------------------------------------------------------------------------------
 // Transmit the command (to the tag) that was placed in ToSend[].
-//-----------------------------------------------------------------------------
-static void TransmitFor14443a(const uint8_t *cmd, int len, int *samples, int *wait)
-{
-  int c;
+// Parameter timing:
+// if NULL: transfer at next possible time, taking into account
+// 			request guard time and frame delay time
+// if == 0:	transfer immediately and return time of transfer
+// if != 0: delay transfer until time specified
+//-------------------------------------------------------------------------------------
+static void TransmitFor14443a(const uint8_t *cmd, uint16_t len, uint32_t *timing) {
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
 
-  FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+	uint32_t ThisTransferTime = 0;
 
-	if (wait)
-    if(*wait < 10)
-      *wait = 10;
+	if (timing) {
+		if(*timing == 0) {										// Measure time
+			*timing = (GetCountSspClk() + 8) & 0xfffffff8;
+		} else {
+			PrepareDelayedTransfer(*timing & 0x00000007);		// Delay transfer (fine tuning - up to 7 MF clock ticks)
+		}
+		if(MF_DBGLEVEL >= 4 && GetCountSspClk() >= (*timing & 0xfffffff8)) Dbprintf("TransmitFor14443a: Missed timing");
+		while(GetCountSspClk() < (*timing & 0xfffffff8));		// Delay transfer (multiple of 8 MF clock ticks)
+		LastTimeProxToAirStart = *timing;
+	} else {
+		ThisTransferTime = ((MAX(NextTransferTime, GetCountSspClk()) & 0xfffffff8) + 8);
 
-  for(c = 0; c < *wait;) {
-    if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-      AT91C_BASE_SSC->SSC_THR = 0x00;		// For exact timing!
-      c++;
-    }
-    if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-      volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
-      (void)r;
-    }
-    WDT_HIT();
-  }
-
-  c = 0;
-  for(;;) {
-    if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-      AT91C_BASE_SSC->SSC_THR = cmd[c];
-      c++;
-      if(c >= len) {
-        break;
-      }
-    }
-    if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-      volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
-      (void)r;
-    }
-    WDT_HIT();
-  }
-	if (samples) *samples = (c + *wait) << 3;
+		while(GetCountSspClk() < ThisTransferTime);
+
+		LastTimeProxToAirStart = ThisTransferTime;
+	}
+	
+	// clear TXRDY
+	AT91C_BASE_SSC->SSC_THR = SEC_Y;
+
+	uint16_t c = 0;
+	for(;;) {
+		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+			AT91C_BASE_SSC->SSC_THR = cmd[c];
+			++c;
+			if(c >= len)
+				break;
+		}
+	}
+	
+	NextTransferTime = MAX(NextTransferTime, LastTimeProxToAirStart + REQUEST_GUARD_TIME);
 }
 
 //-----------------------------------------------------------------------------
-// Code a 7-bit command without parity bit
-// This is especially for 0x26 and 0x52 (REQA and WUPA)
+// Prepare reader command (in bits, support short frames) to send to FPGA
 //-----------------------------------------------------------------------------
-void ShortFrameFromReader(const uint8_t bt)
-{
-	int j;
-	int last;
-  uint8_t b;
+void CodeIso14443aBitsAsReaderPar(const uint8_t *cmd, uint16_t bits, const uint8_t *parity) {
+	int i, j;
+	int last = 0;
+	uint8_t b;
 
 	ToSendReset();
 
 	// Start of Communication (Seq. Z)
 	ToSend[++ToSendMax] = SEC_Z;
-	last = 0;
-
-	b = bt;
-	for(j = 0; j < 7; j++) {
-		if(b & 1) {
-			// Sequence X
-			ToSend[++ToSendMax] = SEC_X;
-			last = 1;
-		} else {
-			if(last == 0) {
+	LastProxToAirDuration = 8 * (ToSendMax+1) - 6;
+
+	size_t bytecount = nbytes(bits);
+	// Generate send structure for the data bits
+	for (i = 0; i < bytecount; i++) {
+		// Get the current byte to send
+		b = cmd[i];
+		size_t bitsleft = MIN((bits-(i*8)),8);
+
+		for (j = 0; j < bitsleft; j++) {
+			if (b & 1) {
+				// Sequence X
+				ToSend[++ToSendMax] = SEC_X;
+				LastProxToAirDuration = 8 * (ToSendMax+1) - 2;
+				last = 1;
+			} else {
+				if (last == 0) {
 				// Sequence Z
 				ToSend[++ToSendMax] = SEC_Z;
+				LastProxToAirDuration = 8 * (ToSendMax+1) - 6;
+				} else {
+					// Sequence Y
+					ToSend[++ToSendMax] = SEC_Y;
+					last = 0;
+				}
 			}
-			else {
-				// Sequence Y
-				ToSend[++ToSendMax] = SEC_Y;
-				last = 0;
+			b >>= 1;
+		}
+
+		// Only transmit parity bit if we transmitted a complete byte
+		if (j == 8 && parity != NULL) {
+			// Get the parity bit
+			if (parity[i>>3] & (0x80 >> (i&0x0007))) {
+				// Sequence X
+				ToSend[++ToSendMax] = SEC_X;
+				LastProxToAirDuration = 8 * (ToSendMax+1) - 2;
+				last = 1;
+			} else {
+				if (last == 0) {
+					// Sequence Z
+					ToSend[++ToSendMax] = SEC_Z;
+					LastProxToAirDuration = 8 * (ToSendMax+1) - 6;
+				} else {
+					// Sequence Y
+					ToSend[++ToSendMax] = SEC_Y;
+					last = 0;
+				}
 			}
 		}
-		b >>= 1;
 	}
 
-	// End of Communication
-	if(last == 0) {
+	// End of Communication: Logic 0 followed by Sequence Y
+	if (last == 0) {
 		// Sequence Z
 		ToSend[++ToSendMax] = SEC_Z;
-	}
-	else {
+		LastProxToAirDuration = 8 * (ToSendMax+1) - 6;
+	} else {
 		// Sequence Y
 		ToSend[++ToSendMax] = SEC_Y;
 		last = 0;
 	}
-	// Sequence Y
-	ToSend[++ToSendMax] = SEC_Y;
-
-	// Just to be sure!
-	ToSend[++ToSendMax] = SEC_Y;
-	ToSend[++ToSendMax] = SEC_Y;
 	ToSend[++ToSendMax] = SEC_Y;
 
-    // Convert from last character reference to length
-    ToSendMax++;
+	// Convert to length of command:
+	++ToSendMax;
 }
 
 //-----------------------------------------------------------------------------
 // Prepare reader command to send to FPGA
-//
 //-----------------------------------------------------------------------------
-void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
-{
-  int i, j;
-  int last;
-  uint8_t b;
-
-  ToSendReset();
-
-  // Start of Communication (Seq. Z)
-  ToSend[++ToSendMax] = SEC_Z;
-  last = 0;
-
-  // Generate send structure for the data bits
-  for (i = 0; i < len; i++) {
-    // Get the current byte to send
-    b = cmd[i];
-
-    for (j = 0; j < 8; j++) {
-      if (b & 1) {
-        // Sequence X
-    	  ToSend[++ToSendMax] = SEC_X;
-        last = 1;
-      } else {
-        if (last == 0) {
-          // Sequence Z
-        	ToSend[++ToSendMax] = SEC_Z;
-        } else {
-          // Sequence Y
-        	ToSend[++ToSendMax] = SEC_Y;
-          last = 0;
-        }
-      }
-      b >>= 1;
-    }
-
-    // Get the parity bit
-    if ((dwParity >> i) & 0x01) {
-      // Sequence X
-    	ToSend[++ToSendMax] = SEC_X;
-      last = 1;
-    } else {
-      if (last == 0) {
-        // Sequence Z
-    	  ToSend[++ToSendMax] = SEC_Z;
-      } else {
-        // Sequence Y
-    	  ToSend[++ToSendMax] = SEC_Y;
-        last = 0;
-      }
-    }
-  }
-
-  // End of Communication
-  if (last == 0) {
-    // Sequence Z
-	  ToSend[++ToSendMax] = SEC_Z;
-  } else {
-    // Sequence Y
-	  ToSend[++ToSendMax] = SEC_Y;
-    last = 0;
-  }
-  // Sequence Y
-  ToSend[++ToSendMax] = SEC_Y;
-
-  // Just to be sure!
-  ToSend[++ToSendMax] = SEC_Y;
-  ToSend[++ToSendMax] = SEC_Y;
-  ToSend[++ToSendMax] = SEC_Y;
-
-  // Convert from last character reference to length
-  ToSendMax++;
+void CodeIso14443aAsReaderPar(const uint8_t *cmd, uint16_t len, const uint8_t *parity) {
+  CodeIso14443aBitsAsReaderPar(cmd, len*8, parity);
 }
 
 //-----------------------------------------------------------------------------
@@ -1458,8 +1559,7 @@ void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
 // Stop when button is pressed (return 1) or field was gone (return 2)
 // Or return 0 when command is captured
 //-----------------------------------------------------------------------------
-static int EmGetCmd(uint8_t *received, int *len, int maxLen)
-{
+static int EmGetCmd(uint8_t *received, uint16_t *len, uint8_t *parity) {
 	*len = 0;
 
 	uint32_t timer = 0, vtime = 0;
@@ -1475,18 +1575,19 @@ static int EmGetCmd(uint8_t *received, int *len, int maxLen)
 	// Set ADC to read field strength
 	AT91C_BASE_ADC->ADC_CR = AT91C_ADC_SWRST;
 	AT91C_BASE_ADC->ADC_MR =
-				ADC_MODE_PRESCALE(32) |
-				ADC_MODE_STARTUP_TIME(16) |
-				ADC_MODE_SAMPLE_HOLD_TIME(8);
+				ADC_MODE_PRESCALE(63) |
+				ADC_MODE_STARTUP_TIME(1) |
+				ADC_MODE_SAMPLE_HOLD_TIME(15);
 	AT91C_BASE_ADC->ADC_CHER = ADC_CHANNEL(ADC_CHAN_HF);
 	// start ADC
 	AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
 	
 	// Now run a 'software UART' on the stream of incoming samples.
-	Uart.output = received;
-	Uart.byteCntMax = maxLen;
-	Uart.state = STATE_UNSYNCD;
+	UartInit(received, parity);
 
+	// Clear RXRDY:
+    uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+	
 	for(;;) {
 		WDT_HIT();
 
@@ -1498,7 +1599,7 @@ static int EmGetCmd(uint8_t *received, int *len, int maxLen)
 			analogAVG += AT91C_BASE_ADC->ADC_CDR[ADC_CHAN_HF];
 			AT91C_BASE_ADC->ADC_CR = AT91C_ADC_START;
 			if (analogCnt >= 32) {
-				if ((33000 * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) {
+				if ((MAX_ADC_HF_VOLTAGE * (analogAVG / analogCnt) >> 10) < MF_MINFIELDV) {
 					vtime = GetTickCount();
 					if (!timer) timer = vtime;
 					// 50ms no field --> card to idle state
@@ -1509,451 +1610,773 @@ static int EmGetCmd(uint8_t *received, int *len, int maxLen)
 				analogAVG = 0;
 			}
 		}
-		// transmit none
-		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-			AT91C_BASE_SSC->SSC_THR = 0x00;
-		}
+
 		// receive and test the miller decoding
-		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-			volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-			if(MillerDecoding((b & 0xf0) >> 4)) {
-				*len = Uart.byteCnt;
-				if (tracing) LogTrace(received, *len, GetDeltaCountUS(), Uart.parityBits, TRUE);
-				return 0;
-			}
-			if(MillerDecoding(b & 0x0f)) {
-				*len = Uart.byteCnt;
-				if (tracing) LogTrace(received, *len, GetDeltaCountUS(), Uart.parityBits, TRUE);
+        if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+            b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+			if(MillerDecoding(b, 0)) {
+				*len = Uart.len;
 				return 0;
 			}
-		}
+        }
 	}
 }
 
-static int EmSendCmd14443aRaw(uint8_t *resp, int respLen, int correctionNeeded)
-{
-	int i, u = 0;
-	uint8_t b = 0;
-
+int EmSendCmd14443aRaw(uint8_t *resp, uint16_t respLen, bool correctionNeeded) {
+	uint8_t b;
+	uint16_t i = 0;
+	uint32_t ThisTransferTime;
+	
 	// Modulate Manchester
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_MOD);
-	AT91C_BASE_SSC->SSC_THR = 0x00;
-	FpgaSetupSsc();
-	
-	// include correction bit
-	i = 1;
-	if((Uart.parityBits & 0x01) || correctionNeeded) {
-		// 1236, so correction bit needed
-		i = 0;
+
+	// include correction bit if necessary
+	if (Uart.parityBits & 0x01) {
+		correctionNeeded = TRUE;
 	}
+	// 1236, so correction bit needed
+	i = (correctionNeeded) ? 0 : 1;
+
+ 	// clear receiving shift register and holding register
+	while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));
+	b = AT91C_BASE_SSC->SSC_RHR; (void) b;
+	while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));
+	b = AT91C_BASE_SSC->SSC_RHR; (void) b;
 	
+	// wait for the FPGA to signal fdt_indicator == 1 (the FPGA is ready to queue new data in its delay line)
+	for (uint8_t j = 0; j < 5; j++) {	// allow timeout - better late than never
+		while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));
+		if (AT91C_BASE_SSC->SSC_RHR) break;
+	}
+
+	while ((ThisTransferTime = GetCountSspClk()) & 0x00000007);
+
+	// Clear TXRDY:
+	AT91C_BASE_SSC->SSC_THR = SEC_F;
+
 	// send cycle
-	for(;;) {
-		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-			volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-			(void)b;
-		}
+	for(; i < respLen; ) {
 		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-			if(i > respLen) {
-				b = 0xff; // was 0x00
-				u++;
-			} else {
-				b = resp[i];
-				i++;
-			}
-			AT91C_BASE_SSC->SSC_THR = b;
-
-			if(u > 4) break;
-		}
-		if(BUTTON_PRESS()) {
-			break;
+			AT91C_BASE_SSC->SSC_THR = resp[i++];
+			FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
 		}
+	
+		if(BUTTON_PRESS()) break;
 	}
 
+	// Ensure that the FPGA Delay Queue is empty before we switch to TAGSIM_LISTEN again:
+	uint8_t fpga_queued_bits = FpgaSendQueueDelay >> 3;  // twich /8 ??   >>3, 
+	for (i = 0; i <= fpga_queued_bits/8 + 1; ) {
+		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+			AT91C_BASE_SSC->SSC_THR = SEC_F;
+			FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+			i++;
+		}
+	}
+	LastTimeProxToAirStart = ThisTransferTime + (correctionNeeded?8:0);
 	return 0;
 }
 
-int EmSend4bitEx(uint8_t resp, int correctionNeeded){
-  Code4bitAnswerAsTag(resp);
+int EmSend4bitEx(uint8_t resp, bool correctionNeeded){
+	Code4bitAnswerAsTag(resp);
 	int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded);
-  if (tracing) LogTrace(&resp, 1, GetDeltaCountUS(), GetParity(&resp, 1), FALSE);
+	// do the tracing for the previous reader request and this tag answer:
+	uint8_t par[1] = {0x00};
+	GetParity(&resp, 1, par);
+	EmLogTrace(Uart.output, 
+				Uart.len, 
+				Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, 
+				Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 
+				Uart.parity,
+				&resp, 
+				1, 
+				LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG,
+				(LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG, 
+				par);
 	return res;
 }
 
 int EmSend4bit(uint8_t resp){
-	return EmSend4bitEx(resp, 0);
+	return EmSend4bitEx(resp, false);
 }
 
-int EmSendCmdExPar(uint8_t *resp, int respLen, int correctionNeeded, uint32_t par){
-  CodeIso14443aAsTagPar(resp, respLen, par);
+int EmSendCmdExPar(uint8_t *resp, uint16_t respLen, bool correctionNeeded, uint8_t *par){
+	CodeIso14443aAsTagPar(resp, respLen, par);
 	int res = EmSendCmd14443aRaw(ToSend, ToSendMax, correctionNeeded);
-  if (tracing) LogTrace(resp, respLen, GetDeltaCountUS(), par, FALSE);
+	// do the tracing for the previous reader request and this tag answer:
+	EmLogTrace(Uart.output, 
+				Uart.len, 
+				Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, 
+				Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, 
+				Uart.parity,
+				resp, 
+				respLen, 
+				LastTimeProxToAirStart*16 + DELAY_ARM2AIR_AS_TAG,
+				(LastTimeProxToAirStart + LastProxToAirDuration)*16 + DELAY_ARM2AIR_AS_TAG, 
+				par);
 	return res;
 }
 
-int EmSendCmdEx(uint8_t *resp, int respLen, int correctionNeeded){
-	return EmSendCmdExPar(resp, respLen, correctionNeeded, GetParity(resp, respLen));
+int EmSendCmdEx(uint8_t *resp, uint16_t respLen, bool correctionNeeded){
+	uint8_t par[MAX_PARITY_SIZE] = {0x00};
+	GetParity(resp, respLen, par);
+	return EmSendCmdExPar(resp, respLen, correctionNeeded, par);
+}
+
+int EmSendCmd(uint8_t *resp, uint16_t respLen){
+	uint8_t par[MAX_PARITY_SIZE] = {0x00};
+	GetParity(resp, respLen, par);
+	return EmSendCmdExPar(resp, respLen, false, par);
 }
 
-int EmSendCmd(uint8_t *resp, int respLen){
-	return EmSendCmdExPar(resp, respLen, 0, GetParity(resp, respLen));
+int EmSendCmdPar(uint8_t *resp, uint16_t respLen, uint8_t *par){
+	return EmSendCmdExPar(resp, respLen, false, par);
 }
 
-int EmSendCmdPar(uint8_t *resp, int respLen, uint32_t par){
-	return EmSendCmdExPar(resp, respLen, 0, par);
+bool EmLogTrace(uint8_t *reader_data, uint16_t reader_len, uint32_t reader_StartTime, uint32_t reader_EndTime, uint8_t *reader_Parity,
+				 uint8_t *tag_data, uint16_t tag_len, uint32_t tag_StartTime, uint32_t tag_EndTime, uint8_t *tag_Parity)
+{
+	// we cannot exactly measure the end and start of a received command from reader. However we know that the delay from
+	// end of the received command to start of the tag's (simulated by us) answer is n*128+20 or n*128+84 resp.
+	// with n >= 9. The start of the tags answer can be measured and therefore the end of the received command be calculated:
+	uint16_t reader_modlen = reader_EndTime - reader_StartTime;
+	uint16_t approx_fdt = tag_StartTime - reader_EndTime;
+	uint16_t exact_fdt = (approx_fdt - 20 + 32)/64 * 64 + 20;
+	reader_EndTime = tag_StartTime - exact_fdt;
+	reader_StartTime = reader_EndTime - reader_modlen;
+		
+	if (!LogTrace(reader_data, reader_len, reader_StartTime, reader_EndTime, reader_Parity, TRUE))
+		return FALSE;
+	else 
+		return(!LogTrace(tag_data, tag_len, tag_StartTime, tag_EndTime, tag_Parity, FALSE));
+
 }
 
 //-----------------------------------------------------------------------------
 // Wait a certain time for tag response
 //  If a response is captured return TRUE
-//  If it takes to long return FALSE
+//  If it takes too long return FALSE
 //-----------------------------------------------------------------------------
-static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed) //uint8_t *buffer
-{
-	// buffer needs to be 512 bytes
-	int c;
-
+static int GetIso14443aAnswerFromTag(uint8_t *receivedResponse, uint8_t *receivedResponsePar, uint16_t offset) {
+	uint32_t c = 0x00;
+	
 	// Set FPGA mode to "reader listen mode", no modulation (listen
 	// only, since we are receiving, not transmitting).
 	// Signal field is on with the appropriate LED
 	LED_D_ON();
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_LISTEN);
-
+	
 	// Now get the answer from the card
-	Demod.output = receivedResponse;
-	Demod.len = 0;
-	Demod.state = DEMOD_UNSYNCD;
+	DemodInit(receivedResponse, receivedResponsePar);
 
-	uint8_t b;
-	if (elapsed) *elapsed = 0;
+	// clear RXRDY:
+    uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
 
-	c = 0;
 	for(;;) {
 		WDT_HIT();
 
-		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-			AT91C_BASE_SSC->SSC_THR = 0x00;  // To make use of exact timing of next command from reader!!
-			if (elapsed) (*elapsed)++;
-		}
 		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-			if(c < iso14a_timeout) { c++; } else { return FALSE; }
 			b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-			if(ManchesterDecoding((b>>4) & 0xf)) {
-				*samples = ((c - 1) << 3) + 4;
-				return TRUE;
-			}
-			if(ManchesterDecoding(b & 0x0f)) {
-				*samples = c << 3;
+			if(ManchesterDecoding(b, offset, 0)) {
+				NextTransferTime = MAX(NextTransferTime, Demod.endTime - (DELAY_AIR2ARM_AS_READER + DELAY_ARM2AIR_AS_READER)/16 + FRAME_DELAY_TIME_PICC_TO_PCD);
 				return TRUE;
+			} else if (c++ > iso14a_timeout && Demod.state == DEMOD_UNSYNCD) {
+				return FALSE; 
 			}
 		}
 	}
 }
 
-void ReaderTransmitShort(const uint8_t* bt)
-{
-  int wait = 0;
-  int samples = 0;
+void ReaderTransmitBitsPar(uint8_t* frame, uint16_t bits, uint8_t *par, uint32_t *timing) {
 
-  ShortFrameFromReader(*bt);
+	CodeIso14443aBitsAsReaderPar(frame, bits, par);
+	// Send command to tag
+	TransmitFor14443a(ToSend, ToSendMax, timing);
+	if(trigger) LED_A_ON();
+  
+	LogTrace(frame, nbytes(bits), (LastTimeProxToAirStart<<4) + DELAY_ARM2AIR_AS_READER, ((LastTimeProxToAirStart + LastProxToAirDuration)<<4) + DELAY_ARM2AIR_AS_READER, par, TRUE);
+}
 
-  // Select the card
-  TransmitFor14443a(ToSend, ToSendMax, &samples, &wait);
+void ReaderTransmitPar(uint8_t* frame, uint16_t len, uint8_t *par, uint32_t *timing) {
+  ReaderTransmitBitsPar(frame, len*8, par, timing);
+}
 
-  // Store reader command in buffer
-  if (tracing) LogTrace(bt,1,0,GetParity(bt,1),TRUE);
+void ReaderTransmitBits(uint8_t* frame, uint16_t len, uint32_t *timing) {
+	// Generate parity and redirect
+	uint8_t par[MAX_PARITY_SIZE] = {0x00};
+	GetParity(frame, len/8, par);  
+	ReaderTransmitBitsPar(frame, len, par, timing);
 }
 
-void ReaderTransmitPar(uint8_t* frame, int len, uint32_t par)
-{
-  int wait = 0;
-  int samples = 0;
-
-  // This is tied to other size changes
-  // 	uint8_t* frame_addr = ((uint8_t*)BigBuf) + 2024;
-  CodeIso14443aAsReaderPar(frame,len,par);
-
-  // Select the card
-  TransmitFor14443a(ToSend, ToSendMax, &samples, &wait);
-  if(trigger)
-  	LED_A_ON();
-
-  // Store reader command in buffer
-  if (tracing) LogTrace(frame,len,0,par,TRUE);
-}
-
-
-void ReaderTransmit(uint8_t* frame, int len)
-{
-  // Generate parity and redirect
-  ReaderTransmitPar(frame,len,GetParity(frame,len));
+void ReaderTransmit(uint8_t* frame, uint16_t len, uint32_t *timing) {
+	// Generate parity and redirect
+	uint8_t par[MAX_PARITY_SIZE] = {0x00};
+	GetParity(frame, len, par);
+	ReaderTransmitBitsPar(frame, len*8, par, timing);
 }
 
-int ReaderReceive(uint8_t* receivedAnswer)
-{
-  int samples = 0;
-  if (!GetIso14443aAnswerFromTag(receivedAnswer,160,&samples,0)) return FALSE;
-  if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE);
-  if(samples == 0) return FALSE;
-  return Demod.len;
+int ReaderReceiveOffset(uint8_t* receivedAnswer, uint16_t offset, uint8_t *parity) {
+	if (!GetIso14443aAnswerFromTag(receivedAnswer, parity, offset))
+		return FALSE;
+	LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, parity, FALSE);
+	return Demod.len;
 }
 
-int ReaderReceivePar(uint8_t* receivedAnswer, uint32_t * parptr)
-{
-  int samples = 0;
-  if (!GetIso14443aAnswerFromTag(receivedAnswer,160,&samples,0)) return FALSE;
-  if (tracing) LogTrace(receivedAnswer,Demod.len,samples,Demod.parityBits,FALSE);
-	*parptr = Demod.parityBits;
-  if(samples == 0) return FALSE;
-  return Demod.len;
+int ReaderReceive(uint8_t *receivedAnswer, uint8_t *parity) {
+	if (!GetIso14443aAnswerFromTag(receivedAnswer, parity, 0))
+		return FALSE;
+	LogTrace(receivedAnswer, Demod.len, Demod.startTime*16 - DELAY_AIR2ARM_AS_READER, Demod.endTime*16 - DELAY_AIR2ARM_AS_READER, parity, FALSE);
+	return Demod.len;
 }
 
-/* performs iso14443a anticolision procedure
- * fills the uid pointer unless NULL
- * fills resp_data unless NULL */
-int iso14443a_select_card(uint8_t * uid_ptr, iso14a_card_select_t * resp_data, uint32_t * cuid_ptr) {
-	uint8_t wupa[]       = { 0x52 };  // 0x26 - REQA  0x52 - WAKE-UP
-	uint8_t sel_all[]    = { 0x93,0x20 };
-	uint8_t sel_uid[]    = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
-	uint8_t rats[]       = { 0xE0,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0
-
-	uint8_t* resp = (((uint8_t *)BigBuf) + 3560);	// was 3560 - tied to other size changes
+// performs iso14443a anticollision (optional) and card select procedure
+// fills the uid and cuid pointer unless NULL
+// fills the card info record unless NULL
+// if anticollision is false, then the UID must be provided in uid_ptr[] 
+// and num_cascades must be set (1: 4 Byte UID, 2: 7 Byte UID, 3: 10 Byte UID)
+int iso14443a_select_card(byte_t *uid_ptr, iso14a_card_select_t *p_hi14a_card, uint32_t *cuid_ptr, bool anticollision, uint8_t num_cascades) {
+	uint8_t wupa[]       = { ISO14443A_CMD_WUPA };  // 0x26 - ISO14443A_CMD_REQA  0x52 - ISO14443A_CMD_WUPA
+	uint8_t sel_all[]    = { ISO14443A_CMD_ANTICOLL_OR_SELECT,0x20 };
+	uint8_t sel_uid[]    = { ISO14443A_CMD_ANTICOLL_OR_SELECT,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
+	uint8_t rats[]       = { ISO14443A_CMD_RATS,0x80,0x00,0x00 }; // FSD=256, FSDI=8, CID=0
+	uint8_t resp[MAX_FRAME_SIZE] = {0}; // theoretically. A usual RATS will be much smaller
+	uint8_t resp_par[MAX_PARITY_SIZE] = {0};
+	byte_t uid_resp[4] = {0};
+	size_t uid_resp_len = 0;
 
 	uint8_t sak = 0x04; // cascade uid
 	int cascade_level = 0;
-
 	int len;
-	
-	// clear uid
-	memset(uid_ptr, 0, 8);
 
 	// Broadcast for a card, WUPA (0x52) will force response from all cards in the field
-	ReaderTransmitShort(wupa);
+    ReaderTransmitBitsPar(wupa, 7, NULL, NULL);
+	
 	// Receive the ATQA
-	if(!ReaderReceive(resp)) return 0;
+	if(!ReaderReceive(resp, resp_par)) return 0;
+
+	if(p_hi14a_card) {
+		memcpy(p_hi14a_card->atqa, resp, 2);
+		p_hi14a_card->uidlen = 0;
+		memset(p_hi14a_card->uid,0,10);
+	}
+
+	if (anticollision) {
+		// clear uid
+		if (uid_ptr)
+			memset(uid_ptr,0,10);
+	}
 
-	if(resp_data)
-		memcpy(resp_data->atqa, resp, 2);
+	// reset the PCB block number
+	iso14_pcb_blocknum = 0;
+	
+	// check for proprietary anticollision:
+	if ((resp[0] & 0x1F) == 0) return 3;
 	
 	// OK we will select at least at cascade 1, lets see if first byte of UID was 0x88 in
 	// which case we need to make a cascade 2 request and select - this is a long UID
 	// While the UID is not complete, the 3nd bit (from the right) is set in the SAK.
-	for(; sak & 0x04; cascade_level++)
-	{
+	for(; sak & 0x04; cascade_level++) {
 		// SELECT_* (L1: 0x93, L2: 0x95, L3: 0x97)
 		sel_uid[0] = sel_all[0] = 0x93 + cascade_level * 2;
 
+		if (anticollision) {
 		// SELECT_ALL
-		ReaderTransmit(sel_all,sizeof(sel_all));
-		if (!ReaderReceive(resp)) return 0;
-		if(uid_ptr) memcpy(uid_ptr + cascade_level*4, resp, 4);
-		
-		// calculate crypto UID
-		if(cuid_ptr) *cuid_ptr = bytes_to_num(resp, 4);
+			ReaderTransmit(sel_all, sizeof(sel_all), NULL);
+			if (!ReaderReceive(resp, resp_par)) return 0;
+
+			if (Demod.collisionPos) {			// we had a collision and need to construct the UID bit by bit
+				memset(uid_resp, 0, 4);
+				uint16_t uid_resp_bits = 0;
+				uint16_t collision_answer_offset = 0;
+				// anti-collision-loop:
+				while (Demod.collisionPos) {
+					Dbprintf("Multiple tags detected. Collision after Bit %d", Demod.collisionPos);
+					for (uint16_t i = collision_answer_offset; i < Demod.collisionPos; i++, uid_resp_bits++) {	// add valid UID bits before collision point
+						uint16_t UIDbit = (resp[i/8] >> (i % 8)) & 0x01;
+						uid_resp[uid_resp_bits / 8] |= UIDbit << (uid_resp_bits % 8);
+					}
+					uid_resp[uid_resp_bits/8] |= 1 << (uid_resp_bits % 8);					// next time select the card(s) with a 1 in the collision position
+					uid_resp_bits++;
+					// construct anticollosion command:
+					sel_uid[1] = ((2 + uid_resp_bits/8) << 4) | (uid_resp_bits & 0x07);  	// length of data in bytes and bits
+					for (uint16_t i = 0; i <= uid_resp_bits/8; i++) {
+						sel_uid[2+i] = uid_resp[i];
+					}
+					collision_answer_offset = uid_resp_bits%8;
+					ReaderTransmitBits(sel_uid, 16 + uid_resp_bits, NULL);
+					if (!ReaderReceiveOffset(resp, collision_answer_offset, resp_par)) return 0;
+				}
+				// finally, add the last bits and BCC of the UID
+				for (uint16_t i = collision_answer_offset; i < (Demod.len-1)*8; i++, uid_resp_bits++) {
+					uint16_t UIDbit = (resp[i/8] >> (i%8)) & 0x01;
+					uid_resp[uid_resp_bits/8] |= UIDbit << (uid_resp_bits % 8);
+				}
+
+			} else {		// no collision, use the response to SELECT_ALL as current uid
+				memcpy(uid_resp, resp, 4);
+			}
+			
+		} else {
+			if (cascade_level < num_cascades - 1) {
+				uid_resp[0] = 0x88;
+				memcpy(uid_resp+1, uid_ptr+cascade_level*3, 3);
+			} else {
+				memcpy(uid_resp, uid_ptr+cascade_level*3, 4);
+			}
+		}
+		uid_resp_len = 4;
+
+		// calculate crypto UID. Always use last 4 Bytes.
+		if(cuid_ptr)
+			*cuid_ptr = bytes_to_num(uid_resp, 4);
 
 		// Construct SELECT UID command
-		memcpy(sel_uid+2,resp,5);
-		AppendCrc14443a(sel_uid,7);
-		ReaderTransmit(sel_uid,sizeof(sel_uid));
+		sel_uid[1] = 0x70;													// transmitting a full UID (1 Byte cmd, 1 Byte NVB, 4 Byte UID, 1 Byte BCC, 2 Bytes CRC)
+		memcpy(sel_uid+2, uid_resp, 4);										// the UID received during anticollision, or the provided UID
+		sel_uid[6] = sel_uid[2] ^ sel_uid[3] ^ sel_uid[4] ^ sel_uid[5];  	// calculate and add BCC
+		AppendCrc14443a(sel_uid, 7);										// calculate and add CRC
+		ReaderTransmit(sel_uid, sizeof(sel_uid), NULL);
 
 		// Receive the SAK
-		if (!ReaderReceive(resp)) return 0;
+		if (!ReaderReceive(resp, resp_par)) return 0;
+		
 		sak = resp[0];
+
+		// Test if more parts of the uid are coming
+		if ((sak & 0x04) /* && uid_resp[0] == 0x88 */) {
+			// Remove first byte, 0x88 is not an UID byte, it CT, see page 3 of:
+			// http://www.nxp.com/documents/application_note/AN10927.pdf
+			uid_resp[0] = uid_resp[1];
+			uid_resp[1] = uid_resp[2];
+			uid_resp[2] = uid_resp[3]; 
+			uid_resp_len = 3;
+		}
+
+		if(uid_ptr && anticollision)
+			memcpy(uid_ptr + (cascade_level*3), uid_resp, uid_resp_len);
+
+		if(p_hi14a_card) {
+			memcpy(p_hi14a_card->uid + (cascade_level*3), uid_resp, uid_resp_len);
+			p_hi14a_card->uidlen += uid_resp_len;
+		}
 	}
-	if(resp_data) {
-		resp_data->sak = sak;
-		resp_data->ats_len = 0;
-	}
-	//--  this byte not UID, it CT.  http://www.nxp.com/documents/application_note/AN10927.pdf  page 3
-	if (uid_ptr[0] == 0x88) {  
-		memcpy(uid_ptr, uid_ptr + 1, 7);
-		uid_ptr[7] = 0;
+
+	if(p_hi14a_card) {
+		p_hi14a_card->sak = sak;
+		p_hi14a_card->ats_len = 0;
 	}
 
-	if( (sak & 0x20) == 0)
-		return 2; // non iso14443a compliant tag
+	// non iso14443a compliant tag
+	if( (sak & 0x20) == 0) return 2; 
 
 	// Request for answer to select
-	if(resp_data) {  // JCOP cards - if reader sent RATS then there is no MIFARE session at all!!!
-		AppendCrc14443a(rats, 2);
-		ReaderTransmit(rats, sizeof(rats));
-		
-		if (!(len = ReaderReceive(resp))) return 0;
-		
-		memcpy(resp_data->ats, resp, sizeof(resp_data->ats));
-		resp_data->ats_len = len;
-	}
+	AppendCrc14443a(rats, 2);
+	ReaderTransmit(rats, sizeof(rats), NULL);
+
+	if (!(len = ReaderReceive(resp, resp_par))) return 0;
 	
-	return 1;
+	if(p_hi14a_card) {
+		memcpy(p_hi14a_card->ats, resp, sizeof(p_hi14a_card->ats));
+		p_hi14a_card->ats_len = len;
+	}
+
+	// set default timeout based on ATS
+	iso14a_set_ATS_timeout(resp);
+	return 1;	
 }
 
-void iso14443a_setup() {
-	// Setup SSC
-	FpgaSetupSsc();
-	// Start from off (no field generated)
-	// Signal field is off with the appropriate LED
-	LED_D_OFF();
-	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-	SpinDelay(200);
+void iso14443a_setup(uint8_t fpga_minor_mode) {
 
+	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+	// Set up the synchronous serial port
+	FpgaSetupSsc();
+	// connect Demodulated Signal to ADC:
 	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
 
-	// Now give it time to spin up.
+	LED_D_OFF();
 	// Signal field is on with the appropriate LED
-	LED_D_ON();
-	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
-	SpinDelay(200);
+	if (fpga_minor_mode == FPGA_HF_ISO14443A_READER_MOD ||
+		fpga_minor_mode == FPGA_HF_ISO14443A_READER_LISTEN)
+		LED_D_ON();
 
-	iso14a_timeout = 2048; //default
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | fpga_minor_mode);
+
+	SpinDelay(20);
+	
+	// Start the timer
+	StartCountSspClk();
+	
+	// Prepare the demodulation functions
+	DemodReset();
+	UartReset();
+	NextTransferTime = 2 * DELAY_ARM2AIR_AS_READER;
+	iso14a_set_timeout(10*106); // 20ms default	
 }
 
-int iso14_apdu(uint8_t * cmd, size_t cmd_len, void * data) {
+int iso14_apdu(uint8_t *cmd, uint16_t cmd_len, void *data) {
+	uint8_t parity[MAX_PARITY_SIZE] = {0x00};
 	uint8_t real_cmd[cmd_len+4];
 	real_cmd[0] = 0x0a; //I-Block
+	// put block number into the PCB
+	real_cmd[0] |= iso14_pcb_blocknum;
 	real_cmd[1] = 0x00; //CID: 0 //FIXME: allow multiple selected cards
 	memcpy(real_cmd+2, cmd, cmd_len);
 	AppendCrc14443a(real_cmd,cmd_len+2);
  
-	ReaderTransmit(real_cmd, cmd_len+4);
-	size_t len = ReaderReceive(data);
-	if(!len)
-		return -1; //DATA LINK ERROR
+	ReaderTransmit(real_cmd, cmd_len+4, NULL);
+	size_t len = ReaderReceive(data, parity);
+	 //DATA LINK ERROR
+	if (!len) return 0;
 	
+	uint8_t *data_bytes = (uint8_t *) data;
+
+	// if we received an I- or R(ACK)-Block with a block number equal to the
+	// current block number, toggle the current block number
+	if (len >= 4 // PCB+CID+CRC = 4 bytes
+	         && ((data_bytes[0] & 0xC0) == 0 // I-Block
+	             || (data_bytes[0] & 0xD0) == 0x80) // R-Block with ACK bit set to 0
+	         && (data_bytes[0] & 0x01) == iso14_pcb_blocknum) // equal block numbers
+	{
+		iso14_pcb_blocknum ^= 1;
+	}
+
 	return len;
 }
 
 
 //-----------------------------------------------------------------------------
 // Read an ISO 14443a tag. Send out commands and store answers.
-//
 //-----------------------------------------------------------------------------
-void ReaderIso14443a(UsbCommand * c, UsbCommand * ack)
-{
+void ReaderIso14443a(UsbCommand *c) {
 	iso14a_command_t param = c->arg[0];
-	uint8_t * cmd = c->d.asBytes;
-	size_t len = c->arg[1];
-
-	if(param & ISO14A_REQUEST_TRIGGER) iso14a_set_trigger(1);
-
-	if(param & ISO14A_CONNECT) {
-		iso14443a_setup();
-		ack->arg[0] = iso14443a_select_card(ack->d.asBytes, (iso14a_card_select_t *) (ack->d.asBytes+12), NULL);
-		UsbSendPacket((void *)ack, sizeof(UsbCommand));
-	}
-
-	if(param & ISO14A_SET_TIMEOUT) {
-		iso14a_timeout = c->arg[2];
+	size_t len = c->arg[1] & 0xffff;
+	size_t lenbits = c->arg[1] >> 16;
+	uint32_t timeout = c->arg[2];
+	uint8_t *cmd = c->d.asBytes;
+	uint32_t arg0 = 0;
+	byte_t buf[USB_CMD_DATA_SIZE] = {0x00};
+	uint8_t par[MAX_PARITY_SIZE] = {0x00};
+  
+	if (param & ISO14A_CONNECT)
+		clear_trace();
+
+	set_tracing(TRUE);
+
+	if (param & ISO14A_REQUEST_TRIGGER)
+		iso14a_set_trigger(TRUE);
+
+	if (param & ISO14A_CONNECT) {
+		iso14443a_setup(FPGA_HF_ISO14443A_READER_LISTEN);
+		if(!(param & ISO14A_NO_SELECT)) {
+			iso14a_card_select_t *card = (iso14a_card_select_t*)buf;
+			arg0 = iso14443a_select_card(NULL,card,NULL, true, 0);
+			cmd_send(CMD_ACK, arg0, card->uidlen, 0, buf, sizeof(iso14a_card_select_t));
+			// if it fails,  the cmdhf14a.c client quites.. however this one still executes.
+			if ( arg0 == 0 ) return;
+		}
 	}
 
-	if(param & ISO14A_SET_TIMEOUT) {
-		iso14a_timeout = c->arg[2];
-	}
+	if (param & ISO14A_SET_TIMEOUT)
+		iso14a_set_timeout(timeout);
 
-	if(param & ISO14A_APDU) {
-		ack->arg[0] = iso14_apdu(cmd, len, ack->d.asBytes);
-		UsbSendPacket((void *)ack, sizeof(UsbCommand));
+	if (param & ISO14A_APDU) {
+		arg0 = iso14_apdu(cmd, len, buf);
+		cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
 	}
 
-	if(param & ISO14A_RAW) {
+	if (param & ISO14A_RAW) {
 		if(param & ISO14A_APPEND_CRC) {
-			AppendCrc14443a(cmd,len);
+			if(param & ISO14A_TOPAZMODE) {
+				AppendCrc14443b(cmd,len);
+			} else {
+				AppendCrc14443a(cmd,len);
+			}
 			len += 2;
+			if (lenbits) lenbits += 16;
+		}
+		if(lenbits>0) {				// want to send a specific number of bits (e.g. short commands)
+			if(param & ISO14A_TOPAZMODE) {
+				int bits_to_send = lenbits;
+				uint16_t i = 0;
+				ReaderTransmitBitsPar(&cmd[i++], MIN(bits_to_send, 7), NULL, NULL);		// first byte is always short (7bits) and no parity
+				bits_to_send -= 7;
+				while (bits_to_send > 0) {
+					ReaderTransmitBitsPar(&cmd[i++], MIN(bits_to_send, 8), NULL, NULL);	// following bytes are 8 bit and no parity
+					bits_to_send -= 8;
+				}
+			} else {
+			GetParity(cmd, lenbits/8, par);
+				ReaderTransmitBitsPar(cmd, lenbits, par, NULL);							// bytes are 8 bit with odd parity
+			}
+		} else {					// want to send complete bytes only
+			if(param & ISO14A_TOPAZMODE) {
+				uint16_t i = 0;
+				ReaderTransmitBitsPar(&cmd[i++], 7, NULL, NULL);						// first byte: 7 bits, no paritiy
+				while (i < len) {
+					ReaderTransmitBitsPar(&cmd[i++], 8, NULL, NULL);					// following bytes: 8 bits, no paritiy
+				}
+		} else {
+				ReaderTransmit(cmd,len, NULL);											// 8 bits, odd parity
+			}
 		}
-		ReaderTransmit(cmd,len);
-		ack->arg[0] = ReaderReceive(ack->d.asBytes);
-		UsbSendPacket((void *)ack, sizeof(UsbCommand));
+		arg0 = ReaderReceive(buf, par);
+		cmd_send(CMD_ACK,arg0,0,0,buf,sizeof(buf));
 	}
 
-	if(param & ISO14A_REQUEST_TRIGGER) iso14a_set_trigger(0);
+	if (param & ISO14A_REQUEST_TRIGGER)
+		iso14a_set_trigger(FALSE);
 
-	if(param & ISO14A_NO_DISCONNECT)
+	if (param & ISO14A_NO_DISCONNECT)
 		return;
 
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+	set_tracing(FALSE);
 	LEDsoff();
 }
+
+// Determine the distance between two nonces.
+// Assume that the difference is small, but we don't know which is first.
+// Therefore try in alternating directions.
+int32_t dist_nt(uint32_t nt1, uint32_t nt2) {
+
+	if (nt1 == nt2) return 0;
+	
+	uint32_t nttmp1 = nt1;
+	uint32_t nttmp2 = nt2;
+
+	// 0xFFFF -- Half up and half down to find distance between nonces
+	for (uint16_t i = 1; i < 32768/8; i += 8) {
+		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i;
+		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+1;
+		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+2;
+		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+3;
+		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+4;
+		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+5;
+		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+6;
+		nttmp1 = prng_successor(nttmp1, 1);	if (nttmp1 == nt2) return i+7;
+		
+		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -i;
+		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+1);
+		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+2);
+		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+3);
+		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+4);
+		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+5);
+		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+6);
+		nttmp2 = prng_successor(nttmp2, 1);	if (nttmp2 == nt1) return -(i+7);		
+	}
+	// either nt1 or nt2 are invalid nonces	
+	return(-99999); 
+}
+
 //-----------------------------------------------------------------------------
-// Read an ISO 14443a tag. Send out commands and store answers.
-//
+// Recover several bits of the cypher stream. This implements (first stages of)
+// the algorithm described in "The Dark Side of Security by Obscurity and
+// Cloning MiFare Classic Rail and Building Passes, Anywhere, Anytime"
+// (article by Nicolas T. Courtois, 2009)
 //-----------------------------------------------------------------------------
-void ReaderMifare(uint32_t parameter)
-{
-	// Mifare AUTH
-	uint8_t mf_auth[]    = { 0x60,0x00,0xf5,0x7b };
-	uint8_t mf_nr_ar[]   = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
 
-	uint8_t* receivedAnswer = (((uint8_t *)BigBuf) + 3560);	// was 3560 - tied to other size changes
-	traceLen = 0;
-	tracing = false;
+void ReaderMifare(bool first_try, uint8_t block, uint8_t keytype ) {
+	
+	uint8_t mf_auth[] 	= { keytype, block, 0x00, 0x00 };
+	uint8_t mf_nr_ar[]	= { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
+	uint8_t uid[10]		= {0,0,0,0,0,0,0,0,0,0};
+	uint8_t par_list[8]	= {0,0,0,0,0,0,0,0};
+	uint8_t ks_list[8]	= {0,0,0,0,0,0,0,0};
+	uint8_t receivedAnswer[MAX_MIFARE_FRAME_SIZE] = {0x00};
+	uint8_t receivedAnswerPar[MAX_MIFARE_PARITY_SIZE] = {0x00};
+	uint8_t par[1] = {0};	// maximum 8 Bytes to be sent here, 1 byte parity is therefore enough
+	byte_t nt_diff = 0;
+	uint32_t nt = 0;
+	uint32_t previous_nt = 0;	
+	uint32_t cuid = 0;
+	
+	int32_t catch_up_cycles = 0;
+	int32_t last_catch_up = 0;
+	int32_t isOK = 0;
+	int32_t nt_distance = 0;
+	
+	uint16_t elapsed_prng_sequences = 1;
+	uint16_t consecutive_resyncs = 0;
+	uint16_t unexpected_random = 0;
+	uint16_t sync_tries = 0;
+
+	// static variables here, is re-used in the next call
+	static uint32_t nt_attacked = 0;
+	static uint32_t sync_time = 0;
+	static uint32_t sync_cycles = 0;
+	static uint8_t par_low = 0;
+	static uint8_t mf_nr_ar3 = 0;
+	
+	#define PRNG_SEQUENCE_LENGTH	(1 << 16)
+	#define MAX_UNEXPECTED_RANDOM	4		// maximum number of unexpected (i.e. real) random numbers when trying to sync. Then give up.
+	#define MAX_SYNC_TRIES		32
+	
+	AppendCrc14443a(mf_auth, 2);
+	
+	BigBuf_free(); BigBuf_Clear_ext(false);	
+	clear_trace();
+	set_tracing(FALSE);	
+	iso14443a_setup(FPGA_HF_ISO14443A_READER_MOD);
+
+	sync_time = GetCountSspClk() & 0xfffffff8;
+	sync_cycles = PRNG_SEQUENCE_LENGTH; // Mifare Classic's random generator repeats every 2^16 cycles (and so do the nonces).		
+	nt_attacked = 0;
+	
+   if (MF_DBGLEVEL >= 4)	Dbprintf("Mifare::Sync %u", sync_time);
+				
+	if (first_try) {
+		mf_nr_ar3 = 0;
+		par_low = 0;
+	} else {
+		// we were unsuccessful on a previous call. 
+		// Try another READER nonce (first 3 parity bits remain the same)
+		++mf_nr_ar3;
+		mf_nr_ar[3] = mf_nr_ar3;
+		par[0] = par_low;
+	}
 
-	iso14443a_setup();
+	bool have_uid = FALSE;
+	uint8_t cascade_levels = 0;
 
-	LED_A_ON();
-	LED_B_OFF();
-	LED_C_OFF();
+	LED_C_ON(); 
+	uint16_t i;
+	for(i = 0; TRUE; ++i) {
 
-	byte_t nt_diff = 0;
-	LED_A_OFF();
-	byte_t par = 0;
-	byte_t par_mask = 0xff;
-	byte_t par_low = 0;
-	int led_on = TRUE;
-	uint8_t uid[8];
-	uint32_t cuid;
-
-	tracing = FALSE;
-	byte_t nt[4] = {0,0,0,0};
-	byte_t nt_attacked[4], nt_noattack[4];
-	byte_t par_list[8] = {0,0,0,0,0,0,0,0};
-	byte_t ks_list[8] = {0,0,0,0,0,0,0,0};
-	num_to_bytes(parameter, 4, nt_noattack);
-	int isOK = 0, isNULL = 0;
-
-	while(TRUE)
-	{
-		LED_C_ON();
-		FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-		SpinDelay(200);
-		FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
-		LED_C_OFF();
+		WDT_HIT();
 
 		// Test if the action was cancelled
 		if(BUTTON_PRESS()) {
+			isOK = -1;
 			break;
 		}
+		
+		// this part is from Piwi's faster nonce collecting part in Hardnested.
+		if (!have_uid) { // need a full select cycle to get the uid first
+			iso14a_card_select_t card_info;		
+			if(!iso14443a_select_card(uid, &card_info, &cuid, true, 0)) {
+				if (MF_DBGLEVEL >= 4)	Dbprintf("Mifare: Can't select card (ALL)");
+				break;
+			}
+			switch (card_info.uidlen) {
+				case 4 : cascade_levels = 1; break;
+				case 7 : cascade_levels = 2; break;
+				case 10: cascade_levels = 3; break;
+				default: break;
+			}
+			have_uid = TRUE;	
+		} else { // no need for anticollision. We can directly select the card
+			if(!iso14443a_select_card(uid, NULL, &cuid, false, cascade_levels)) {
+				if (MF_DBGLEVEL >= 4)	Dbprintf("Mifare: Can't select card (UID)");
+				continue;
+			}
+		}
+		
+		// Sending timeslot of ISO14443a frame		
+		sync_time = (sync_time & 0xfffffff8 ) + sync_cycles + catch_up_cycles;
+		catch_up_cycles = 0;
+								
+		// if we missed the sync time already, advance to the next nonce repeat
+		while( GetCountSspClk() > sync_time) {
+			++elapsed_prng_sequences;
+			sync_time = (sync_time & 0xfffffff8 ) + sync_cycles;
+		}		
+
+		// Transmit MIFARE_CLASSIC_AUTH at synctime. Should result in returning the same tag nonce (== nt_attacked)
+		ReaderTransmit(mf_auth, sizeof(mf_auth), &sync_time);
+
+		// Receive the (4 Byte) "random" nonce from TAG
+		if (!ReaderReceive(receivedAnswer, receivedAnswerPar))
+			continue;
+
+		previous_nt = nt;
+		nt = bytes_to_num(receivedAnswer, 4);
+		
+		// Transmit reader nonce with fake par
+		ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar), par, NULL);
+	
+		// we didn't calibrate our clock yet,
+		// iceman: has to be calibrated every time.
+		if (previous_nt && !nt_attacked) { 
 
-		if(!iso14443a_select_card(uid, NULL, &cuid)) continue;
-
-		// Transmit MIFARE_CLASSIC_AUTH
-		ReaderTransmit(mf_auth, sizeof(mf_auth));
-
-		// Receive the (16 bit) "random" nonce
-		if (!ReaderReceive(receivedAnswer)) continue;
-		memcpy(nt, receivedAnswer, 4);
-
-		// Transmit reader nonce and reader answer
-		ReaderTransmitPar(mf_nr_ar, sizeof(mf_nr_ar),par);
+			nt_distance = dist_nt(previous_nt, nt);
+			
+			// if no distance between,  then we are in sync.
+			if (nt_distance == 0) {
+				nt_attacked = nt;
+			} else {
+				if (nt_distance == -99999) { // invalid nonce received
+					++unexpected_random;
+					if (unexpected_random > MAX_UNEXPECTED_RANDOM) {
+						isOK = -3;		// Card has an unpredictable PRNG. Give up	
+						break;
+					} else {						
+						if (sync_cycles <= 0) sync_cycles += PRNG_SEQUENCE_LENGTH;
+						LED_B_OFF();
+						continue;		// continue trying...
+					}
+				}
+				
+				if (++sync_tries > MAX_SYNC_TRIES) {
+					isOK = -4; 			// Card's PRNG runs at an unexpected frequency or resets unexpectedly
+					break;
+				}
+				
+				sync_cycles = (sync_cycles - nt_distance)/elapsed_prng_sequences;
+				
+				if (sync_cycles <= 0)
+					sync_cycles += PRNG_SEQUENCE_LENGTH;
+				
+				if (MF_DBGLEVEL >= 4)
+					Dbprintf("calibrating in cycle %d. nt_distance=%d, elapsed_prng_sequences=%d, new sync_cycles: %d\n", i, nt_distance, elapsed_prng_sequences, sync_cycles);
 
-		// Receive 4 bit answer
-		if (ReaderReceive(receivedAnswer))
-		{
-			if ( (parameter != 0) && (memcmp(nt, nt_noattack, 4) == 0) ) continue;
+				LED_B_OFF();
+				continue;
+			}
+		}
+		LED_B_OFF();
 
-			isNULL = (nt_attacked[0] = 0) && (nt_attacked[1] = 0) && (nt_attacked[2] = 0) && (nt_attacked[3] = 0);
-			if ( (isNULL != 0 ) && (memcmp(nt, nt_attacked, 4) != 0) ) continue;
+		if ( (nt != nt_attacked) && nt_attacked) { 	// we somehow lost sync. Try to catch up again...
+			
+			catch_up_cycles = ABS(dist_nt(nt_attacked, nt));
+			if (catch_up_cycles == 99999) {			// invalid nonce received. Don't resync on that one.
+				catch_up_cycles = 0;
+				continue;
+			}		
+			// average? 
+			catch_up_cycles /= elapsed_prng_sequences;
+		
+			if (catch_up_cycles == last_catch_up) {
+				++consecutive_resyncs;
+			} else {
+				last_catch_up = catch_up_cycles;
+			    consecutive_resyncs = 0;
+			}		
+			
+			if (consecutive_resyncs < 3) {
+				if (MF_DBGLEVEL >= 4)
+					Dbprintf("Lost sync in cycle %d. nt_distance=%d. Consecutive Resyncs = %d. Trying one time catch up...\n", i, catch_up_cycles, consecutive_resyncs);
+			} else {	
+				sync_cycles += catch_up_cycles;
+				
+				if (MF_DBGLEVEL >= 4) 
+					Dbprintf("Lost sync in cycle %d for the fourth time consecutively (nt_distance = %d). Adjusting sync_cycles to %d.\n", i, catch_up_cycles, sync_cycles);
 
-			if (nt_diff == 0)
-			{
-				LED_A_ON();
-				memcpy(nt_attacked, nt, 4);
-				par_mask = 0xf8;
-				par_low = par & 0x07;
+				last_catch_up = 0;
+				catch_up_cycles = 0;
+				consecutive_resyncs = 0;
 			}
+			continue;
+		}
+ 
+		// Receive answer. This will be a 4 Bit NACK when the 8 parity bits are OK after decoding
+		if (ReaderReceive(receivedAnswer, receivedAnswerPar)) {
+			catch_up_cycles = 8; 	// the PRNG is delayed by 8 cycles due to the NAC (4Bits = 0x05 encrypted) transfer
+	
+			if (nt_diff == 0)
+				par_low = par[0] & 0xE0; // there is no need to check all parities for other nt_diff. Parity Bits for mf_nr_ar[0..2] won't change
 
-			led_on = !led_on;
-			if(led_on) LED_B_ON(); else LED_B_OFF();
-			par_list[nt_diff] = par;
-			ks_list[nt_diff] = receivedAnswer[0] ^ 0x05;
+			par_list[nt_diff] = SwapBits(par[0], 8);
+			ks_list[nt_diff] = receivedAnswer[0] ^ 0x05;  // xor with NACK value to get keystream
 
 			// Test if the information is complete
 			if (nt_diff == 0x07) {
@@ -1962,310 +2385,515 @@ void ReaderMifare(uint32_t parameter)
 			}
 
 			nt_diff = (nt_diff + 1) & 0x07;
-			mf_nr_ar[3] = nt_diff << 5;
-			par = par_low;
+			mf_nr_ar[3] = (mf_nr_ar[3] & 0x1F) | (nt_diff << 5);
+			par[0] = par_low;
+			
 		} else {
-			if (nt_diff == 0)
-			{
-				par++;
+			// No NACK.	
+			if (nt_diff == 0 && first_try) {
+				par[0]++;
+				if (par[0] == 0x00) {	// tried all 256 possible parities without success. Card doesn't send NACK.
+					isOK = -2;
+					break;
+				}
 			} else {
-				par = (((par >> 3) + 1) << 3) | par_low;
+				// Why this?
+				par[0] = ((par[0] & 0x1F) + 1) | par_low;
 			}
 		}
-	}
+		
+		// reset the resyncs since we got a complete transaction on right time.
+		consecutive_resyncs = 0;
+	} // end for loop
 
-	LogTrace(nt, 4, 0, GetParity(nt, 4), TRUE);
-	LogTrace(par_list, 8, 0, GetParity(par_list, 8), TRUE);
-	LogTrace(ks_list, 8, 0, GetParity(ks_list, 8), TRUE);
+	mf_nr_ar[3] &= 0x1F;
 
-	UsbCommand ack = {CMD_ACK, {isOK, 0, 0}};
-	memcpy(ack.d.asBytes + 0,  uid, 4);
-	memcpy(ack.d.asBytes + 4,  nt, 4);
-	memcpy(ack.d.asBytes + 8,  par_list, 8);
-	memcpy(ack.d.asBytes + 16, ks_list, 8);
+	if (MF_DBGLEVEL >= 4) Dbprintf("Number of sent auth requestes: %u", i);
+	
+	uint8_t buf[28] = {0x00};
+	memset(buf, 0x00, sizeof(buf));
+	num_to_bytes(cuid, 4, buf);
+	num_to_bytes(nt, 4, buf + 4);
+	memcpy(buf + 8,  par_list, 8);
+	memcpy(buf + 16, ks_list, 8);
+	memcpy(buf + 24, mf_nr_ar, 4);
 		
-	LED_B_ON();
-	UsbSendPacket((uint8_t *)&ack, sizeof(UsbCommand));
-	LED_B_OFF();	
+	cmd_send(CMD_ACK, isOK, 0, 0, buf, sizeof(buf) );
 
-	// Thats it...
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
 	LEDsoff();
-	tracing = TRUE;
-	
-	if (MF_DBGLEVEL >= 1)	DbpString("COMMAND mifare FINISHED");
+	set_tracing(FALSE);
 }
 
 
-//-----------------------------------------------------------------------------
-// MIFARE 1K simulate. 
-// 
-//-----------------------------------------------------------------------------
-void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain)
-{
+/**
+  *MIFARE 1K simulate.
+  *
+  *@param flags :
+  *	FLAG_INTERACTIVE		- In interactive mode, we are expected to finish the operation with an ACK
+  * FLAG_4B_UID_IN_DATA		- use 4-byte UID in the data-section
+  * FLAG_7B_UID_IN_DATA		- use 7-byte UID in the data-section
+  * FLAG_10B_UID_IN_DATA	- use 10-byte UID in the data-section
+  * FLAG_UID_IN_EMUL 		- use 4-byte UID from emulator memory
+  *	FLAG_NR_AR_ATTACK  		- collect NR_AR responses for bruteforcing later
+  *@param exitAfterNReads, exit simulation after n blocks have been read, 0 is inifite
+  */
+void Mifare1ksim(uint8_t flags, uint8_t exitAfterNReads, uint8_t arg2, uint8_t *datain) {
 	int cardSTATE = MFEMUL_NOFIELD;
-	int _7BUID = 0;
+	int _UID_LEN = 0;  // 4, 7, 10
 	int vHf = 0;	// in mV
-	int nextCycleTimeout = 0;
-	int res;
-//	uint32_t timer = 0;
+	int res = 0;
 	uint32_t selTimer = 0;
 	uint32_t authTimer = 0;
-	uint32_t par = 0;
-	int len = 0;
+	uint16_t len = 0;
 	uint8_t cardWRBL = 0;
 	uint8_t cardAUTHSC = 0;
 	uint8_t cardAUTHKEY = 0xff;  // no authentication
-	uint32_t cardRn = 0;
-	uint32_t cardRr = 0;
 	uint32_t cuid = 0;
-	uint32_t rn_enc = 0;
 	uint32_t ans = 0;
+	uint32_t cardINTREG = 0;
+	uint8_t cardINTBLOCK = 0;
 	struct Crypto1State mpcs = {0, 0};
 	struct Crypto1State *pcs;
 	pcs = &mpcs;
+	uint32_t numReads = 0;	// Counts numer of times reader read a block
+	uint8_t receivedCmd[MAX_MIFARE_FRAME_SIZE] = {0x00};
+	uint8_t receivedCmd_par[MAX_MIFARE_PARITY_SIZE] = {0x00};
+	uint8_t response[MAX_MIFARE_FRAME_SIZE] = {0x00};
+	uint8_t response_par[MAX_MIFARE_PARITY_SIZE] = {0x00};
 	
-	uint8_t* receivedCmd = eml_get_bigbufptr_recbuf();
-	uint8_t *response = eml_get_bigbufptr_sendbuf();
+	uint8_t atqa[]   = {0x04, 0x00}; // Mifare classic 1k
+	uint8_t sak_4[]  = {0x0C, 0x00, 0x00}; // CL1 - 4b uid
+	uint8_t sak_7[]  = {0x0C, 0x00, 0x00}; // CL2 - 7b uid
+	uint8_t sak_10[] = {0x0C, 0x00, 0x00}; // CL3 - 10b uid
+	// uint8_t sak[] = {0x09, 0x3f, 0xcc };  // Mifare Mini 
 	
-	static uint8_t rATQA[] = {0x04, 0x00}; // Mifare classic 1k 4BUID
+	uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; 
+	uint8_t rUIDBCC2[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; 
+	uint8_t rUIDBCC3[] = {0xde, 0xad, 0xbe, 0xaf, 0x62};
 
-	static uint8_t rUIDBCC1[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; 
-	static uint8_t rUIDBCC2[] = {0xde, 0xad, 0xbe, 0xaf, 0x62}; // !!!
+	uint8_t rAUTH_NT[] = {0x01, 0x01, 0x01, 0x01};	// very random nonce
+	// uint8_t rAUTH_NT[] = {0x55, 0x41, 0x49, 0x92};// nonce from nested? why this?
+	uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00};
 		
-	static uint8_t rSAK[] = {0x08, 0xb6, 0xdd};
-	static uint8_t rSAK1[] = {0x04, 0xda, 0x17};
-
-	static uint8_t rAUTH_NT[] = {0x1a, 0xac, 0xff, 0x4f};
-	static uint8_t rAUTH_AT[] = {0x00, 0x00, 0x00, 0x00};
-	
-	// clear trace
-	traceLen = 0;
-	tracing = true;
-
-  // Authenticate response - nonce
+	// Here, we collect CUID, NT, NR, AR, CUID2, NT2, NR2, AR2
+	// This can be used in a reader-only attack.
+	nonces_t ar_nr_resp[ATTACK_KEY_COUNT*2]; // for 2 separate attack types (nml, moebius)
+	memset(ar_nr_resp, 0x00, sizeof(ar_nr_resp));
+
+	uint8_t ar_nr_collected[ATTACK_KEY_COUNT*2]; // for 2nd attack type (moebius)
+	memset(ar_nr_collected, 0x00, sizeof(ar_nr_collected));
+	uint8_t	nonce1_count = 0;
+	uint8_t	nonce2_count = 0;
+	uint8_t	moebius_n_count = 0;
+	bool gettingMoebius = false;
+	uint8_t	mM = 0; // moebius_modifier for collection storage
+	bool doBufResetNext = false;
+
+	// Authenticate response - nonce
 	uint32_t nonce = bytes_to_num(rAUTH_NT, 4);
 	
-	// get UID from emul memory
-	emlGetMemBt(receivedCmd, 7, 1);
-	_7BUID = !(receivedCmd[0] == 0x00);
-	if (!_7BUID) {                     // ---------- 4BUID
-		rATQA[0] = 0x04;
-
-		emlGetMemBt(rUIDBCC1, 0, 4);
-		rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
-	} else {                           // ---------- 7BUID
-		rATQA[0] = 0x44;
-
-		rUIDBCC1[0] = 0x88;
-		emlGetMemBt(&rUIDBCC1[1], 0, 3);
-		rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
-		emlGetMemBt(rUIDBCC2, 3, 4);
-		rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3];
+	// -- Determine the UID
+	// Can be set from emulator memory or incoming data
+	// Length: 4,7,or 10 bytes
+	if ( (flags & FLAG_UID_IN_EMUL) == FLAG_UID_IN_EMUL)
+		emlGetMemBt(datain, 0, 10);  // load 10bytes from EMUL to the datain pointer. to be used below.
+	
+	if ( (flags & FLAG_4B_UID_IN_DATA) == FLAG_4B_UID_IN_DATA) {
+		memcpy(rUIDBCC1, datain, 4);
+		_UID_LEN = 4;
+	} else if ( (flags & FLAG_7B_UID_IN_DATA) == FLAG_7B_UID_IN_DATA) {
+		memcpy(&rUIDBCC1[1], datain,   3);
+		memcpy( rUIDBCC2,    datain+3, 4);
+		_UID_LEN = 7;
+	} else if ( (flags & FLAG_10B_UID_IN_DATA) == FLAG_10B_UID_IN_DATA) {
+		memcpy(&rUIDBCC1[1], datain,   3);
+		memcpy(&rUIDBCC2[1], datain+3, 3);
+		memcpy( rUIDBCC3,    datain+6, 4);
+		_UID_LEN = 10;
 	}
 
-// --------------------------------------	test area
-
-// --------------------------------------	END test area
-	// start mkseconds counter
-	StartCountUS();
-
+	switch (_UID_LEN) {
+		case 4:
+			sak_4[0] &= 0xFB;		
+			// save CUID
+			cuid = bytes_to_num(rUIDBCC1, 4);
+			// BCC
+			rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
+			if (MF_DBGLEVEL >= 2)	{
+				Dbprintf("4B UID: %02x%02x%02x%02x", 
+					rUIDBCC1[0],
+					rUIDBCC1[1],
+					rUIDBCC1[2],
+					rUIDBCC1[3]
+				);
+			}
+			break;
+		case 7:
+			atqa[0] |= 0x40;
+			sak_7[0] &= 0xFB;						
+			// save CUID
+			cuid = bytes_to_num(rUIDBCC2, 4);			
+			 // CascadeTag, CT
+			rUIDBCC1[0] = 0x88;
+			// BCC
+			rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3]; 
+			rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3]; 
+			if (MF_DBGLEVEL >= 2)	{
+				Dbprintf("7B UID: %02x %02x %02x %02x %02x %02x %02x",
+					rUIDBCC1[1],
+					rUIDBCC1[2],
+					rUIDBCC1[3],
+					rUIDBCC2[0],
+					rUIDBCC2[1],
+					rUIDBCC2[2],
+					rUIDBCC2[3]
+				);
+			}
+			break;
+		case 10:
+			atqa[0] |= 0x80;
+			sak_10[0] &= 0xFB;					
+			// save CUID
+			cuid = bytes_to_num(rUIDBCC3, 4);
+			 // CascadeTag, CT
+			rUIDBCC1[0] = 0x88;
+			rUIDBCC2[0] = 0x88;
+			// BCC
+			rUIDBCC1[4] = rUIDBCC1[0] ^ rUIDBCC1[1] ^ rUIDBCC1[2] ^ rUIDBCC1[3];
+			rUIDBCC2[4] = rUIDBCC2[0] ^ rUIDBCC2[1] ^ rUIDBCC2[2] ^ rUIDBCC2[3];
+			rUIDBCC3[4] = rUIDBCC3[0] ^ rUIDBCC3[1] ^ rUIDBCC3[2] ^ rUIDBCC3[3];
+
+			if (MF_DBGLEVEL >= 2)	{
+				Dbprintf("10B UID: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
+					rUIDBCC1[1],
+					rUIDBCC1[2],
+					rUIDBCC1[3],
+					rUIDBCC2[1],
+					rUIDBCC2[2],
+					rUIDBCC2[3],
+					rUIDBCC3[0],
+					rUIDBCC3[1],
+					rUIDBCC3[2],
+					rUIDBCC3[3]
+				);
+			}
+			break;
+		default: 
+			break;
+	}
+	// calc some crcs
+	ComputeCrc14443(CRC_14443_A, sak_4, 1, &sak_4[1], &sak_4[2]);
+	ComputeCrc14443(CRC_14443_A, sak_7, 1, &sak_7[1], &sak_7[2]);
+	ComputeCrc14443(CRC_14443_A, sak_10, 1, &sak_10[1], &sak_10[2]);
+	
 	// We need to listen to the high-frequency, peak-detected path.
-	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-	FpgaSetupSsc();
+	iso14443a_setup(FPGA_HF_ISO14443A_TAGSIM_LISTEN);
 
-  FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_TAGSIM_LISTEN);
-	SpinDelay(200);
+	// free eventually allocated BigBuf memory but keep Emulator Memory
+	BigBuf_free_keep_EM();
+	clear_trace();
+	set_tracing(TRUE);
 
-	Dbprintf("--> start. 7buid=%d", _7BUID);
-	// calibrate mkseconds counter
-	GetDeltaCountUS();
-	while (true) {
+	bool finished = FALSE;
+	while (!BUTTON_PRESS() && !finished && !usb_poll_validate_length()) {
 		WDT_HIT();
 
-		if(BUTTON_PRESS()) {
-			break;
-		}
-
 		// find reader field
-		// Vref = 3300mV, and an 10:1 voltage divider on the input
-		// can measure voltages up to 33000 mV
 		if (cardSTATE == MFEMUL_NOFIELD) {
-			vHf = (33000 * AvgAdc(ADC_CHAN_HF)) >> 10;
+			vHf = (MAX_ADC_HF_VOLTAGE * AvgAdc(ADC_CHAN_HF)) >> 10;
 			if (vHf > MF_MINFIELDV) {
-				cardSTATE = MFEMUL_IDLE;
+				cardSTATE_TO_IDLE();
 				LED_A_ON();
 			}
 		} 
-
-		if (cardSTATE != MFEMUL_NOFIELD) {
-			res = EmGetCmd(receivedCmd, &len, 100); // (+ nextCycleTimeout)
-			if (res == 2) {
-				cardSTATE = MFEMUL_NOFIELD;
-				LEDsoff();
-				continue;
-			}
-			if(res) break;
+		if (cardSTATE == MFEMUL_NOFIELD) continue;
+
+		// Now, get data
+		res = EmGetCmd(receivedCmd, &len, receivedCmd_par);
+		if (res == 2) { //Field is off!
+			cardSTATE = MFEMUL_NOFIELD;
+			LEDsoff();
+			continue;
+		} else if (res == 1) {
+			break; 	// return value 1 means button press
 		}
-		
-		nextCycleTimeout = 0;
-		
-//		if (len) Dbprintf("len:%d cmd: %02x %02x %02x %02x", len, receivedCmd[0], receivedCmd[1], receivedCmd[2], receivedCmd[3]);
-
-		if (len != 4 && cardSTATE != MFEMUL_NOFIELD) { // len != 4 <---- speed up the code 4 authentication
-			// REQ or WUP request in ANY state and WUP in HALTED state
-			if (len == 1 && ((receivedCmd[0] == 0x26 && cardSTATE != MFEMUL_HALTED) || receivedCmd[0] == 0x52)) {
-				selTimer = GetTickCount();
-				EmSendCmdEx(rATQA, sizeof(rATQA), (receivedCmd[0] == 0x52));
-				cardSTATE = MFEMUL_SELECT1;
-
-				// init crypto block
-				LED_B_OFF();
-				LED_C_OFF();
-				crypto1_destroy(pcs);
-				cardAUTHKEY = 0xff;
-			}
+			
+		// REQ or WUP request in ANY state and WUP in HALTED state
+		// this if-statement doesn't match the specification above. (iceman)
+		if (len == 1 && ((receivedCmd[0] == ISO14443A_CMD_REQA && cardSTATE != MFEMUL_HALTED) || receivedCmd[0] == ISO14443A_CMD_WUPA)) {
+			selTimer = GetTickCount();
+			EmSendCmdEx(atqa, sizeof(atqa), (receivedCmd[0] == ISO14443A_CMD_WUPA));
+			cardSTATE = MFEMUL_SELECT1;
+			crypto1_destroy(pcs);
+			cardAUTHKEY = 0xff;
+			LEDsoff();
+			nonce++; 
+			continue;
 		}
 		
 		switch (cardSTATE) {
-			case MFEMUL_NOFIELD:{
-				break;
-			}
-			case MFEMUL_HALTED:{
-				break;
-			}
+			case MFEMUL_NOFIELD:
+			case MFEMUL_HALTED:
 			case MFEMUL_IDLE:{
+				LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
 				break;
 			}
 			case MFEMUL_SELECT1:{
-				// select all
-				if (len == 2 && (receivedCmd[0] == 0x93 && receivedCmd[1] == 0x20)) {
+				if (len == 2 && (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT && receivedCmd[1] == 0x20)) {
+					if (MF_DBGLEVEL >= 4)	Dbprintf("SELECT ALL received");
 					EmSendCmd(rUIDBCC1, sizeof(rUIDBCC1));
+					break;
 				}
-
 				// select card
 				if (len == 9 && 
-						(receivedCmd[0] == 0x93 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC1, 4) == 0)) {
-					if (!_7BUID) 
-						EmSendCmd(rSAK, sizeof(rSAK));
-					else
-						EmSendCmd(rSAK1, sizeof(rSAK1));
-
-					cuid = bytes_to_num(rUIDBCC1, 4);
-					if (!_7BUID) {
-						cardSTATE = MFEMUL_WORK;
-					} else {
-						cardSTATE = MFEMUL_SELECT2;
-						break;
+						( receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT &&
+						  receivedCmd[1] == 0x70 && 
+						  memcmp(&receivedCmd[2], rUIDBCC1, 4) == 0)) {
+					
+					// SAK 4b 
+					EmSendCmd(sak_4, sizeof(sak_4));
+					switch(_UID_LEN){
+						case 4:
+							cardSTATE = MFEMUL_WORK;
+							LED_B_ON();
+							if (MF_DBGLEVEL >= 4)	Dbprintf("--> WORK. anticol1 time: %d", GetTickCount() - selTimer);
+							continue;
+						case 7:
+						case 10:
+							cardSTATE = MFEMUL_SELECT2;
+							continue;
+						default:break;
 					}
-					LED_B_ON();
-					if (MF_DBGLEVEL >= 4)	Dbprintf("--> WORK. anticol1 time: %d", GetTickCount() - selTimer);
+				} else {
+					cardSTATE_TO_IDLE();
 				}
-				
 				break;
 			}
 			case MFEMUL_SELECT2:{
-				if (len == 2 && (receivedCmd[0] == 0x95 && receivedCmd[1] == 0x20)) {
+				if (!len) { 
+					LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+					break;
+				}
+				if (len == 2 && (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_2 && receivedCmd[1] == 0x20)) {
 					EmSendCmd(rUIDBCC2, sizeof(rUIDBCC2));
 					break;
 				}
-
-				// select 2 card
 				if (len == 9 && 
-						(receivedCmd[0] == 0x95 && receivedCmd[1] == 0x70 && memcmp(&receivedCmd[2], rUIDBCC2, 4) == 0)) {
-					EmSendCmd(rSAK, sizeof(rSAK));
+						(receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_2 &&
+						 receivedCmd[1] == 0x70 && 
+						 memcmp(&receivedCmd[2], rUIDBCC2, 4) == 0) ) {
+							 
+					EmSendCmd(sak_7, sizeof(sak_7));
+					switch(_UID_LEN){
+						case 7:
+							cardSTATE = MFEMUL_WORK;
+							LED_B_ON();
+							if (MF_DBGLEVEL >= 4)	Dbprintf("--> WORK. anticol2 time: %d", GetTickCount() - selTimer);
+							continue;
+						case 10:
+							cardSTATE = MFEMUL_SELECT3;
+							continue;
+						default:break;
+					}
+				} 
+				cardSTATE_TO_IDLE();
+				break;
+			}
+			case MFEMUL_SELECT3:{
+				if (!len) { 
+					LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+					break;
+				}
+				if (len == 2 && (receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_3 && receivedCmd[1] == 0x20)) {
+					EmSendCmd(rUIDBCC3, sizeof(rUIDBCC3));
+					break;
+				}
+				if (len == 9 && 
+						(receivedCmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_3 &&
+						 receivedCmd[1] == 0x70 && 
+						 memcmp(&receivedCmd[2], rUIDBCC3, 4) == 0) ) {
 
-					cuid = bytes_to_num(rUIDBCC2, 4);
+					EmSendCmd(sak_10, sizeof(sak_10));
 					cardSTATE = MFEMUL_WORK;
 					LED_B_ON();
-					Dbprintf("--> WORK. anticol2 time: %d", GetTickCount() - selTimer);
+					if (MF_DBGLEVEL >= 4)	Dbprintf("--> WORK. anticol3 time: %d", GetTickCount() - selTimer);
 					break;
 				}
-				// TODO: goto work state - i guess there is a command
+				cardSTATE_TO_IDLE();
 				break;
 			}
 			case MFEMUL_AUTH1:{
-				if (len == 8) {
-					// --- crypto
-					rn_enc = bytes_to_num(receivedCmd, 4);
-					cardRn = rn_enc ^ crypto1_word(pcs, rn_enc , 1);
-					cardRr = bytes_to_num(&receivedCmd[4], 4) ^ crypto1_word(pcs, 0, 0);
-					// test if auth OK
-					if (cardRr != prng_successor(nonce, 64)){
-						Dbprintf("AUTH FAILED. cardRr=%08x, suc=%08x", cardRr, prng_successor(nonce, 64));
-						cardSTATE = MFEMUL_IDLE;
-						LED_B_OFF();
-						LED_C_OFF();
+				if( len != 8) {
+					cardSTATE_TO_IDLE();
+					LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+					break;
+				}
+
+				uint32_t nr = bytes_to_num(receivedCmd, 4);
+				uint32_t ar = bytes_to_num(&receivedCmd[4], 4);
+
+				if (doBufResetNext) {
+					// Reset, lets try again!
+					Dbprintf("Re-read after previous NR_AR_ATTACK, resetting buffer");
+					memset(ar_nr_resp, 0x00, sizeof(ar_nr_resp));
+					memset(ar_nr_collected, 0x00, sizeof(ar_nr_collected));
+					mM = 0;
+					doBufResetNext = false;
+				}
+
+				for (uint8_t i = 0; i < ATTACK_KEY_COUNT; i++) {
+					if ( ar_nr_collected[i+mM]==0 || ((cardAUTHSC == ar_nr_resp[i+mM].sector) && (cardAUTHKEY == ar_nr_resp[i+mM].keytype) && (ar_nr_collected[i+mM] > 0)) ) {
+
+						// if first auth for sector, or matches sector and keytype of previous auth
+						if (ar_nr_collected[i+mM] < 2) {
+							// if we haven't already collected 2 nonces for this sector
+							if (ar_nr_resp[ar_nr_collected[i+mM]].ar != ar) {
+								// Avoid duplicates... probably not necessary, ar should vary.
+								if (ar_nr_collected[i+mM]==0) {
+									// first nonce collect
+									ar_nr_resp[i+mM].cuid = cuid;
+									ar_nr_resp[i+mM].sector = cardAUTHSC;
+									ar_nr_resp[i+mM].keytype = cardAUTHKEY;
+									ar_nr_resp[i+mM].nonce = nonce;
+									ar_nr_resp[i+mM].nr = nr;
+									ar_nr_resp[i+mM].ar = ar;
+									nonce1_count++;
+									// add this nonce to first moebius nonce
+									ar_nr_resp[i+ATTACK_KEY_COUNT].cuid = cuid;
+									ar_nr_resp[i+ATTACK_KEY_COUNT].sector = cardAUTHSC;
+									ar_nr_resp[i+ATTACK_KEY_COUNT].keytype = cardAUTHKEY;
+									ar_nr_resp[i+ATTACK_KEY_COUNT].nonce = nonce;
+									ar_nr_resp[i+ATTACK_KEY_COUNT].nr = nr;
+									ar_nr_resp[i+ATTACK_KEY_COUNT].ar = ar;
+									ar_nr_collected[i+ATTACK_KEY_COUNT]++;
+								} else { // second nonce collect (std and moebius)
+									ar_nr_resp[i+mM].nonce2 = nonce;
+									ar_nr_resp[i+mM].nr2 = nr;
+									ar_nr_resp[i+mM].ar2 = ar;
+									if (!gettingMoebius) {
+										nonce2_count++;
+										// check if this was the last second nonce we need for std attack
+										if ( nonce2_count == nonce1_count ) {
+											// done collecting std test switch to moebius
+											// first finish incrementing last sample
+											ar_nr_collected[i+mM]++; 
+											// switch to moebius collection
+											gettingMoebius = true;
+											mM = ATTACK_KEY_COUNT;
+											break;
+										}
+									} else {
+										moebius_n_count++;
+										// if we've collected all the nonces we need - finish.
+
+										if (nonce1_count == moebius_n_count) {
+											cmd_send(CMD_ACK,CMD_SIMULATE_MIFARE_CARD,0,0,&ar_nr_resp,sizeof(ar_nr_resp));
+											nonce1_count = 0;
+											nonce2_count = 0;
+											moebius_n_count = 0;
+											gettingMoebius = false;
+											doBufResetNext = true;
+											finished = ( ((flags & FLAG_INTERACTIVE) == FLAG_INTERACTIVE));
+										}
+									}
+								}
+								ar_nr_collected[i+mM]++;
+							}
+						}
+						// we found right spot for this nonce stop looking
 						break;
 					}
-					ans = prng_successor(nonce, 96) ^ crypto1_word(pcs, 0, 0);
-					num_to_bytes(ans, 4, rAUTH_AT);
-					// --- crypto
-					EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
-					cardSTATE = MFEMUL_AUTH2;
-				} else {
-					cardSTATE = MFEMUL_IDLE;
-					LED_B_OFF();
-					LED_C_OFF();
 				}
-				if (cardSTATE != MFEMUL_AUTH2) break;
-			}
-			case MFEMUL_AUTH2:{
-				// test auth info here...
 
+
+				/*
+				// Collect AR/NR
+				// if(ar_nr_collected < 2 && cardAUTHSC == 2){
+				if(ar_nr_collected < 2) {					
+					// if(ar_nr_responses[2] != nr) {
+						ar_nr_responses[ar_nr_collected*4]   = cuid;
+						ar_nr_responses[ar_nr_collected*4+1] = nonce;
+						ar_nr_responses[ar_nr_collected*4+2] = nr;
+						ar_nr_responses[ar_nr_collected*4+3] = ar;
+						ar_nr_collected++;
+					// }					
+		
+					// Interactive mode flag, means we need to send ACK
+					finished = ( ((flags & FLAG_INTERACTIVE) == FLAG_INTERACTIVE)&& ar_nr_collected == 2);
+				}
+				
+				crypto1_word(pcs, ar , 1);
+				cardRr = nr ^ crypto1_word(pcs, 0, 0);
+				
+				test if auth OK
+				if (cardRr != prng_successor(nonce, 64)){
+					
+					if (MF_DBGLEVEL >= 4) Dbprintf("AUTH FAILED for sector %d with key %c. cardRr=%08x, succ=%08x",
+						cardAUTHSC, cardAUTHKEY == 0 ? 'A' : 'B',
+							cardRr, prng_successor(nonce, 64));
+					Shouldn't we respond anything here?
+					Right now, we don't nack or anything, which causes the
+					reader to do a WUPA after a while. /Martin
+					-- which is the correct response. /piwi
+					cardSTATE_TO_IDLE();
+					LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+					break;
+				}
+				*/
+				
+				ans = prng_successor(nonce, 96) ^ crypto1_word(pcs, 0, 0);
+				num_to_bytes(ans, 4, rAUTH_AT);
+				EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
 				LED_C_ON();
+				
+				if (MF_DBGLEVEL >= 4) {
+					Dbprintf("AUTH COMPLETED for sector %d with key %c. time=%d", 
+						cardAUTHSC, 
+						cardAUTHKEY == 0 ? 'A' : 'B',
+						GetTickCount() - authTimer
+					);
+				}
 				cardSTATE = MFEMUL_WORK;
-				Dbprintf("AUTH COMPLETED. sec=%d, key=%d time=%d", cardAUTHSC, cardAUTHKEY, GetTickCount() - authTimer);
 				break;
 			}
 			case MFEMUL_WORK:{
-				if (len == 0) break;
-				
-				if (cardAUTHKEY == 0xff) {
-					// first authentication
-					if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) {
-						authTimer = GetTickCount();
-
-						cardAUTHSC = receivedCmd[1] / 4;  // received block num
-						cardAUTHKEY = receivedCmd[0] - 0x60;
-
-						// --- crypto
-						crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
-						ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0); 
-						num_to_bytes(nonce, 4, rAUTH_AT);
-						EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
-						// --- crypto
-						
-//   last working revision 
-//						EmSendCmd14443aRaw(resp1, resp1Len, 0);
-//						LogTrace(NULL, 0, GetDeltaCountUS(), 0, true);
+				if (len == 0) {
+					LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+					break;
+				}		
+				bool encrypted_data = (cardAUTHKEY != 0xFF) ;
 
-						cardSTATE = MFEMUL_AUTH1;
-						nextCycleTimeout = 10;
-						break;
-					}
-				} else {
-					// decrypt seqence
+				if(encrypted_data)
 					mf_crypto1_decrypt(pcs, receivedCmd, len);
-					
-					// nested authentication
-					if (len == 4 && (receivedCmd[0] == 0x60 || receivedCmd[0] == 0x61)) {
-						authTimer = GetTickCount();
-
-						cardAUTHSC = receivedCmd[1] / 4;  // received block num
-						cardAUTHKEY = receivedCmd[0] - 0x60;
+				
+				if (len == 4 && (receivedCmd[0] == MIFARE_AUTH_KEYA || 
+				                 receivedCmd[0] == MIFARE_AUTH_KEYB)  ) {
+
+					authTimer = GetTickCount();
+					cardAUTHSC = receivedCmd[1] / 4;  // received block num
+					cardAUTHKEY = receivedCmd[0] - 0x60; // & 1
+					crypto1_destroy(pcs);
+					crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
+
+					if (!encrypted_data) { 
+						// first authentication
+						crypto1_word(pcs, cuid ^ nonce, 0);// Update crypto state
+						num_to_bytes(nonce, 4, rAUTH_AT); // Send nonce
+						
+						if (MF_DBGLEVEL >= 4) Dbprintf("Reader authenticating for block %d (0x%02x) with key %d",receivedCmd[1] ,receivedCmd[1],cardAUTHKEY  );
 
-						// --- crypto
-						crypto1_create(pcs, emlGetKey(cardAUTHSC, cardAUTHKEY));
+					} else {
+						// nested authentication
 						ans = nonce ^ crypto1_word(pcs, cuid ^ nonce, 0); 
 						num_to_bytes(ans, 4, rAUTH_AT);
-						EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
-						// --- crypto
 
-						cardSTATE = MFEMUL_AUTH1;
-						nextCycleTimeout = 10;
-						break;
+						if (MF_DBGLEVEL >= 4) Dbprintf("Reader doing nested authentication for block %d (0x%02x) with key %d",receivedCmd[1] ,receivedCmd[1],cardAUTHKEY );
 					}
+
+					EmSendCmd(rAUTH_AT, sizeof(rAUTH_AT));
+					cardSTATE = MFEMUL_AUTH1;
+					break;
 				}
 				
 				// rule 13 of 7.5.3. in ISO 14443-4. chaining shall be continued
@@ -2281,76 +2909,359 @@ void Mifare1ksim(uint8_t arg0, uint8_t arg1, uint8_t arg2, uint8_t *datain)
 					break;
 				}
 				
-				// read block
-				if (len == 4 && receivedCmd[0] == 0x30) {
-					if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) {
+				if(len != 4) {
+					LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+					break;
+				}
+
+				if ( receivedCmd[0] == ISO14443A_CMD_READBLOCK ||
+					 receivedCmd[0] == ISO14443A_CMD_WRITEBLOCK ||
+					 receivedCmd[0] == MIFARE_CMD_INC ||
+					 receivedCmd[0] == MIFARE_CMD_DEC ||
+					 receivedCmd[0] == MIFARE_CMD_RESTORE ||
+					 receivedCmd[0] == MIFARE_CMD_TRANSFER ) {
+						
+					if (receivedCmd[1] >= 16 * 4) {
+						EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
+						if (MF_DBGLEVEL >= 4) Dbprintf("Reader tried to operate (0x%02) on out of range block: %d (0x%02x), nacking",receivedCmd[0],receivedCmd[1],receivedCmd[1]);
+						break;
+					}
+
+					if (receivedCmd[1] / 4 != cardAUTHSC) {
 						EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
+						if (MF_DBGLEVEL >= 4) Dbprintf("Reader tried to operate (0x%02) on block (0x%02x) not authenticated for (0x%02x), nacking",receivedCmd[0],receivedCmd[1],cardAUTHSC);
 						break;
 					}
+				}
+				// read block
+				if (receivedCmd[0] == ISO14443A_CMD_READBLOCK) {
+					if (MF_DBGLEVEL >= 4) Dbprintf("Reader reading block %d (0x%02x)", receivedCmd[1], receivedCmd[1]);
+
 					emlGetMem(response, receivedCmd[1], 1);
 					AppendCrc14443a(response, 16);
-					mf_crypto1_encrypt(pcs, response, 18, &par);
-					EmSendCmdPar(response, 18, par);
+					mf_crypto1_encrypt(pcs, response, 18, response_par);
+					EmSendCmdPar(response, 18, response_par);
+					numReads++;
+					if(exitAfterNReads > 0 && numReads >= exitAfterNReads) {
+						Dbprintf("%d reads done, exiting", numReads);
+						finished = true;
+					}
 					break;
 				}
-				
 				// write block
-				if (len == 4 && receivedCmd[0] == 0xA0) {
-					if (receivedCmd[1] >= 16 * 4 || receivedCmd[1] / 4 != cardAUTHSC) {
+				if (receivedCmd[0] == ISO14443A_CMD_WRITEBLOCK) {
+					if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0xA0 write block %d (%02x)", receivedCmd[1], receivedCmd[1]);
+					EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
+					cardSTATE = MFEMUL_WRITEBL2;
+					cardWRBL = receivedCmd[1];
+					break;
+				}
+				// increment, decrement, restore
+				if ( receivedCmd[0] == MIFARE_CMD_INC || 
+				     receivedCmd[0] == MIFARE_CMD_DEC || 
+					 receivedCmd[0] == MIFARE_CMD_RESTORE) {
+
+					 if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0x%02x inc(0xC1)/dec(0xC0)/restore(0xC2) block %d (%02x)",receivedCmd[0], receivedCmd[1], receivedCmd[1]);
+
+					if (emlCheckValBl(receivedCmd[1])) {
+						if (MF_DBGLEVEL >= 4) Dbprintf("Reader tried to operate on block, but emlCheckValBl failed, nacking");
 						EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
 						break;
 					}
 					EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
-					nextCycleTimeout = 50;
-					cardSTATE = MFEMUL_WRITEBL2;
+					if (receivedCmd[0] == MIFARE_CMD_INC)		cardSTATE = MFEMUL_INTREG_INC;
+					if (receivedCmd[0] == MIFARE_CMD_DEC)		cardSTATE = MFEMUL_INTREG_DEC;
+					if (receivedCmd[0] == MIFARE_CMD_RESTORE)	cardSTATE = MFEMUL_INTREG_REST;
 					cardWRBL = receivedCmd[1];
 					break;
 				}
-			
+				// transfer
+				if (receivedCmd[0] == MIFARE_CMD_TRANSFER) {
+					if (MF_DBGLEVEL >= 4) Dbprintf("RECV 0x%02x transfer block %d (%02x)", receivedCmd[0], receivedCmd[1], receivedCmd[1]);
+					if (emlSetValBl(cardINTREG, cardINTBLOCK, receivedCmd[1]))
+						EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
+					else
+						EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
+					break;
+				}
 				// halt
-				if (len == 4 && (receivedCmd[0] == 0x50 && receivedCmd[1] == 0x00)) {
-					cardSTATE = MFEMUL_HALTED;
+				if (receivedCmd[0] == ISO14443A_CMD_HALT && receivedCmd[1] == 0x00) {
 					LED_B_OFF();
 					LED_C_OFF();
-					Dbprintf("--> HALTED. Selected time: %d ms",  GetTickCount() - selTimer);
+					cardSTATE = MFEMUL_HALTED;
+					if (MF_DBGLEVEL >= 4)	Dbprintf("--> HALTED. Selected time: %d ms",  GetTickCount() - selTimer);
+					LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
 					break;
 				}
-				
-				// command not allowed
-				if (len == 4) {
+				// RATS
+				if (receivedCmd[0] == ISO14443A_CMD_RATS) {
 					EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
 					break;
 				}
-
-				// case break
+				// command not allowed
+				if (MF_DBGLEVEL >= 4)	Dbprintf("Received command not allowed, nacking");
+				EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
 				break;
 			}
 			case MFEMUL_WRITEBL2:{
-				if (len == 18){
+				if (len == 18) {
 					mf_crypto1_decrypt(pcs, receivedCmd, len);
 					emlSetMem(receivedCmd, cardWRBL, 1);
 					EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_ACK));
 					cardSTATE = MFEMUL_WORK;
-					break;
 				} else {
-					cardSTATE = MFEMUL_IDLE;
-					LED_B_OFF();
-					LED_C_OFF();
+					cardSTATE_TO_IDLE();
+					LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+				}
+				break;
+			}
+			case MFEMUL_INTREG_INC:{
+				mf_crypto1_decrypt(pcs, receivedCmd, len);
+				memcpy(&ans, receivedCmd, 4);
+				if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
+					EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
+					cardSTATE_TO_IDLE();
+					break;
+				} 
+				LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+				cardINTREG = cardINTREG + ans;
+				cardSTATE = MFEMUL_WORK;
+				break;
+			}
+			case MFEMUL_INTREG_DEC:{
+				mf_crypto1_decrypt(pcs, receivedCmd, len);
+				memcpy(&ans, receivedCmd, 4);
+				if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
+					EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
+					cardSTATE_TO_IDLE();
 					break;
 				}
+				LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+				cardINTREG = cardINTREG - ans;
+				cardSTATE = MFEMUL_WORK;
+				break;
+			}
+			case MFEMUL_INTREG_REST:{
+				mf_crypto1_decrypt(pcs, receivedCmd, len);
+				memcpy(&ans, receivedCmd, 4);
+				if (emlGetValBl(&cardINTREG, &cardINTBLOCK, cardWRBL)) {
+					EmSend4bit(mf_crypto1_encrypt4bit(pcs, CARD_NACK_NA));
+					cardSTATE_TO_IDLE();
+					break;
+				}
+				LogTrace(Uart.output, Uart.len, Uart.startTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.endTime*16 - DELAY_AIR2ARM_AS_TAG, Uart.parity, TRUE);
+				cardSTATE = MFEMUL_WORK;
 				break;
 			}
-		
 		}
-	
 	}
 
+	// Interactive mode flag, means we need to send ACK
+	/*
+	if((flags & FLAG_INTERACTIVE) == FLAG_INTERACTIVE) {
+		// May just aswell send the collected ar_nr in the response aswell
+		uint8_t len = ar_nr_collected * 4 * 4;
+		cmd_send(CMD_ACK, CMD_SIMULATE_MIFARE_CARD, len, 0, &ar_nr_responses, len);
+	}
+	
+   */
+	if( ((flags & FLAG_NR_AR_ATTACK) == FLAG_NR_AR_ATTACK ) && MF_DBGLEVEL >= 1 ) {
+		for ( uint8_t	i = 0; i < ATTACK_KEY_COUNT; i++) {
+			if (ar_nr_collected[i] == 2) {
+				Dbprintf("Collected two pairs of AR/NR which can be used to extract %s from reader for sector %d:", (i<ATTACK_KEY_COUNT/2) ? "keyA" : "keyB", ar_nr_resp[i].sector);
+				Dbprintf("../tools/mfkey/mfkey32 %08x %08x %08x %08x %08x %08x",
+						ar_nr_resp[i].cuid,  //UID
+						ar_nr_resp[i].nonce, //NT
+						ar_nr_resp[i].nr,    //NR1
+						ar_nr_resp[i].ar,    //AR1
+						ar_nr_resp[i].nr2,   //NR2
+						ar_nr_resp[i].ar2    //AR2
+						);
+			}
+		}	
+		for ( uint8_t i = ATTACK_KEY_COUNT; i < ATTACK_KEY_COUNT*2; i++) {
+			if (ar_nr_collected[i] == 2) {
+				Dbprintf("Collected two pairs of AR/NR which can be used to extract %s from reader for sector %d:", (i<ATTACK_KEY_COUNT/2) ? "keyA" : "keyB", ar_nr_resp[i].sector);
+				Dbprintf("../tools/mfkey/mfkey32v2 %08x %08x %08x %08x %08x %08x %08x",
+						ar_nr_resp[i].cuid,  //UID
+						ar_nr_resp[i].nonce, //NT
+						ar_nr_resp[i].nr,    //NR1
+						ar_nr_resp[i].ar,    //AR1
+						ar_nr_resp[i].nonce2,//NT2
+						ar_nr_resp[i].nr2,   //NR2
+						ar_nr_resp[i].ar2    //AR2
+						);
+			}
+		}
+	}
+	
+	
+	if (MF_DBGLEVEL >= 1) Dbprintf("Emulator stopped. Tracing: %d  trace length: %d ", tracing, BigBuf_get_traceLen());
+	
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
 	LEDsoff();
+	set_tracing(FALSE);
+}
+
+
+//-----------------------------------------------------------------------------
+// MIFARE sniffer. 
+// 
+// if no activity for 2sec, it sends the collected data to the client.
+//-----------------------------------------------------------------------------
+// "hf mf sniff"
+void RAMFUNC SniffMifare(uint8_t param) {
+
+	LEDsoff();
+
+	// free eventually allocated BigBuf memory
+	BigBuf_free(); BigBuf_Clear_ext(false);
+	clear_trace();
+	set_tracing(TRUE);
+
+	// The command (reader -> tag) that we're receiving.
+	uint8_t receivedCmd[MAX_MIFARE_FRAME_SIZE] = {0x00};	
+	uint8_t receivedCmdPar[MAX_MIFARE_PARITY_SIZE] = {0x00};
+
+	// The response (tag -> reader) that we're receiving.
+	uint8_t receivedResponse[MAX_MIFARE_FRAME_SIZE] = {0x00};
+	uint8_t receivedResponsePar[MAX_MIFARE_PARITY_SIZE] = {0x00};
+
+	iso14443a_setup(FPGA_HF_ISO14443A_SNIFFER);
+
+	// allocate the DMA buffer, used to stream samples from the FPGA
+	// [iceman] is this sniffed data unsigned?
+	uint8_t *dmaBuf = BigBuf_malloc(DMA_BUFFER_SIZE);
+	uint8_t *data = dmaBuf;
+	uint8_t previous_data = 0;
+	int maxDataLen = 0;
+	int dataLen = 0;
+	bool ReaderIsActive = FALSE;
+	bool TagIsActive = FALSE;
+
+	// Set up the demodulator for tag -> reader responses.
+	DemodInit(receivedResponse, receivedResponsePar);
+
+	// Set up the demodulator for the reader -> tag commands
+	UartInit(receivedCmd, receivedCmdPar);
+
+	// Setup and start DMA.
+	// set transfer address and number of bytes. Start transfer.
+	if ( !FpgaSetupSscDma((uint8_t*) dmaBuf, DMA_BUFFER_SIZE) ){
+		if (MF_DBGLEVEL > 1) Dbprintf("FpgaSetupSscDma failed. Exiting"); 
+		return;
+	}
+
+	LED_D_OFF();
+
+	MfSniffInit();
+
+	// And now we loop, receiving samples.
+	for(uint32_t sniffCounter = 0;; ) {
+
+		LED_A_ON();
+		WDT_HIT();
+	
+		if(BUTTON_PRESS()) {
+			DbpString("cancelled by button");
+			break;
+		}
+	
+ 		if ((sniffCounter & 0x0000FFFF) == 0) {	// from time to time
+			// check if a transaction is completed (timeout after 2000ms).
+			// if yes, stop the DMA transfer and send what we have so far to the client
+			if (MfSniffSend(2000)) {			
+				// Reset everything - we missed some sniffed data anyway while the DMA was stopped
+				sniffCounter = 0;
+				data = dmaBuf;
+				maxDataLen = 0;
+				ReaderIsActive = FALSE;
+				TagIsActive = FALSE;
+				// Setup and start DMA. set transfer address and number of bytes. Start transfer.
+				if ( !FpgaSetupSscDma((uint8_t*) dmaBuf, DMA_BUFFER_SIZE) ){
+					if (MF_DBGLEVEL > 1) Dbprintf("FpgaSetupSscDma failed. Exiting"); 
+					return;
+				}				
+			}
+		}
+		
+		int register readBufDataP = data - dmaBuf;	// number of bytes we have processed so far
+		int register dmaBufDataP = DMA_BUFFER_SIZE - AT91C_BASE_PDC_SSC->PDC_RCR; // number of bytes already transferred
+
+		if (readBufDataP <= dmaBufDataP)			// we are processing the same block of data which is currently being transferred
+			dataLen = dmaBufDataP - readBufDataP;	// number of bytes still to be processed
+		else
+			dataLen = DMA_BUFFER_SIZE - readBufDataP + dmaBufDataP; // number of bytes still to be processed
+
+		// test for length of buffer
+		if(dataLen > maxDataLen) {					// we are more behind than ever...
+			maxDataLen = dataLen;					
+			if(dataLen > (9 * DMA_BUFFER_SIZE / 10)) {
+				Dbprintf("blew circular buffer! dataLen=0x%x", dataLen);
+				break;
+			}
+		}
+		if(dataLen < 1) continue;
+
+		// primary buffer was stopped ( <-- we lost data!
+		if (!AT91C_BASE_PDC_SSC->PDC_RCR) {
+			AT91C_BASE_PDC_SSC->PDC_RPR = (uint32_t) dmaBuf;
+			AT91C_BASE_PDC_SSC->PDC_RCR = DMA_BUFFER_SIZE;
+			Dbprintf("RxEmpty ERROR, data length:%d", dataLen); // temporary
+		}
+		// secondary buffer sets as primary, secondary buffer was stopped
+		if (!AT91C_BASE_PDC_SSC->PDC_RNCR) {
+			AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf;
+			AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
+		}
+
+		LED_A_OFF();
+		
+		if (sniffCounter & 0x01) {
+
+			// no need to try decoding tag data if the reader is sending
+			if(!TagIsActive) {		
+				uint8_t readerdata = (previous_data & 0xF0) | (*data >> 4);
+				if(MillerDecoding(readerdata, (sniffCounter-1)*4)) {
+					LED_C_INV();
+
+					if (MfSniffLogic(receivedCmd, Uart.len, Uart.parity, Uart.bitCount, TRUE)) break;
 
-	// add trace trailer
-	memset(rAUTH_NT, 0x44, 4);
-	LogTrace(rAUTH_NT, 4, 0, 0, TRUE);
+					UartInit(receivedCmd, receivedCmdPar);
+					DemodReset();
+				}
+				ReaderIsActive = (Uart.state != STATE_UNSYNCD);
+			}
+			
+			// no need to try decoding tag data if the reader is sending
+			if(!ReaderIsActive) {		
+				uint8_t tagdata = (previous_data << 4) | (*data & 0x0F);
+				if(ManchesterDecoding(tagdata, 0, (sniffCounter-1)*4)) {
+					LED_C_INV();
 
-	DbpString("Emulator stopped.");
+					if (MfSniffLogic(receivedResponse, Demod.len, Demod.parity, Demod.bitCount, FALSE)) break;
+
+					DemodReset();
+					UartInit(receivedCmd, receivedCmdPar);
+				}
+				TagIsActive = (Demod.state != DEMOD_UNSYNCD);
+			}
+		}
+
+		previous_data = *data;
+		sniffCounter++;
+		data++;
+
+		if(data == dmaBuf + DMA_BUFFER_SIZE)
+			data = dmaBuf;
+
+	} // main cycle
+	
+	if (MF_DBGLEVEL >= 1) Dbprintf("maxDataLen=%x, Uart.state=%x, Uart.len=%x", maxDataLen, Uart.state, Uart.len);
+	
+	FpgaDisableSscDma();
+	MfSniffEnd();
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+	LEDsoff();
+	set_tracing(FALSE);
 }