X-Git-Url: http://cvs.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/d8af608f8e4e6dc520045bac69e8e9dac6de7d42..e3f9c50d81680809c6cdb821dee419a666ecd2c3:/armsrc/iso14443b.c

diff --git a/armsrc/iso14443b.c b/armsrc/iso14443b.c
index 2bdce7cb..72c71964 100644
--- a/armsrc/iso14443b.c
+++ b/armsrc/iso14443b.c
@@ -13,13 +13,11 @@
 #include "apps.h"
 #include "util.h"
 #include "string.h"
-
 #include "iso14443crc.h"
-
-#define RECEIVE_SAMPLES_TIMEOUT 0x0004FFFF
+#include "common.h"
+#define RECEIVE_SAMPLES_TIMEOUT 20000
 #define ISO14443B_DMA_BUFFER_SIZE 256
 
-uint8_t PowerOn = TRUE;
 // PCB Block number for APDUs
 static uint8_t pcb_blocknum = 0;
 
@@ -31,6 +29,88 @@ static uint8_t pcb_blocknum = 0;
 // a response.
 //=============================================================================
 
+
+//-----------------------------------------------------------------------------
+// The software UART that receives commands from the reader, and its state
+// variables.
+//-----------------------------------------------------------------------------
+static struct {
+	enum {
+		STATE_UNSYNCD,
+		STATE_GOT_FALLING_EDGE_OF_SOF,
+		STATE_AWAITING_START_BIT,
+		STATE_RECEIVING_DATA
+	}       state;
+	uint16_t    shiftReg;
+	int     bitCnt;
+	int     byteCnt;
+	int     byteCntMax;
+	int     posCnt;
+	uint8_t   *output;
+} Uart;
+
+static void UartReset()
+{
+	Uart.byteCntMax = MAX_FRAME_SIZE;
+	Uart.state = STATE_UNSYNCD;
+	Uart.byteCnt = 0;
+	Uart.bitCnt = 0;
+	Uart.posCnt = 0;
+	memset(Uart.output, 0x00, MAX_FRAME_SIZE);
+}
+
+static void UartInit(uint8_t *data)
+{
+	Uart.output = data;
+	UartReset();
+}
+
+
+static struct {
+	enum {
+		DEMOD_UNSYNCD,
+		DEMOD_PHASE_REF_TRAINING,
+		DEMOD_AWAITING_FALLING_EDGE_OF_SOF,
+		DEMOD_GOT_FALLING_EDGE_OF_SOF,
+		DEMOD_AWAITING_START_BIT,
+		DEMOD_RECEIVING_DATA
+	}       state;
+	int     bitCount;
+	int     posCount;
+	int     thisBit;
+/* this had been used to add RSSI (Received Signal Strength Indication) to traces. Currently not implemented.
+	int     metric;
+	int     metricN;
+*/
+	uint16_t    shiftReg;
+	uint8_t   *output;
+	int     len;
+	int     sumI;
+	int     sumQ;
+} Demod;
+
+static void DemodReset()
+{
+	// Clear out the state of the "UART" that receives from the tag.
+	Demod.len = 0;
+	Demod.state = DEMOD_UNSYNCD;
+	Demod.posCount = 0;
+	Demod.sumI = 0;
+	Demod.sumQ = 0;
+	Demod.bitCount = 0;
+	Demod.thisBit = 0;
+	Demod.shiftReg = 0;
+	memset(Demod.output, 0x00, MAX_FRAME_SIZE);
+}
+
+
+static void DemodInit(uint8_t *data)
+{
+	Demod.output = data;
+	DemodReset();
+}
+
+
 //-----------------------------------------------------------------------------
 // Code up a string of octets at layer 2 (including CRC, we don't generate
 // that here) so that they can be transmitted to the reader. Doesn't transmit
@@ -118,24 +198,7 @@ static void CodeIso14443bAsTag(const uint8_t *cmd, int len)
 	ToSendMax++;
 }
 
-//-----------------------------------------------------------------------------
-// The software UART that receives commands from the reader, and its state
-// variables.
-//-----------------------------------------------------------------------------
-static struct {
-	enum {
-		STATE_UNSYNCD,
-		STATE_GOT_FALLING_EDGE_OF_SOF,
-		STATE_AWAITING_START_BIT,
-		STATE_RECEIVING_DATA
-	}       state;
-	uint16_t    shiftReg;
-	int     bitCnt;
-	int     byteCnt;
-	int     byteCntMax;
-	int     posCnt;
-	uint8_t   *output;
-} Uart;
+
 
 /* Receive & handle a bit coming from the reader.
  *
@@ -263,24 +326,6 @@ static RAMFUNC int Handle14443bUartBit(uint8_t bit)
 	return FALSE;
 }
 
-
-static void UartReset()
-{
-	Uart.byteCntMax = MAX_FRAME_SIZE;
-	Uart.state = STATE_UNSYNCD;
-	Uart.byteCnt = 0;
-	Uart.bitCnt = 0;
-	memset(Uart.output, 0x00, MAX_FRAME_SIZE);
-}
-
-
-static void UartInit(uint8_t *data)
-{
-	Uart.output = data;
-	UartReset();
-}
-
-
 //-----------------------------------------------------------------------------
 // Receive a command (from the reader to us, where we are the simulated tag),
 // and store it in the given buffer, up to the given maximum length. Keeps
@@ -345,7 +390,7 @@ void SimulateIso14443bTag(void)
 	// response to HLTB and ATTRIB
 	static const uint8_t response2[] = {0x00, 0x78, 0xF0};
 
-	uint8_t parity[MAX_PARITY_SIZE];
+	//uint8_t parity[MAX_PARITY_SIZE] = {0x00};
 				
 	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
 
@@ -357,7 +402,8 @@ void SimulateIso14443bTag(void)
 	uint16_t respLen, respCodeLen;
 
 	// allocate command receive buffer
-	BigBuf_free();
+	BigBuf_free(); BigBuf_Clear_ext(false);
+	
 	uint8_t *receivedCmd = BigBuf_malloc(MAX_FRAME_SIZE);
 
 	uint16_t len;
@@ -383,14 +429,15 @@ void SimulateIso14443bTag(void)
 
 	for(;;) {
 
-		if(!GetIso14443bCommandFromReader(receivedCmd, &len)) {
-		Dbprintf("button pressed, received %d commands", cmdsRecvd);
-		break;
+		if (!GetIso14443bCommandFromReader(receivedCmd, &len)) {
+			Dbprintf("button pressed, received %d commands", cmdsRecvd);
+			break;
 		}
 
-		if (tracing) {
-			LogTrace(receivedCmd, len, 0, 0, parity, TRUE);
-		}
+		if (tracing)
+			//LogTrace(receivedCmd, len, 0, 0, parity, TRUE);
+			LogTrace(receivedCmd, len, 0, 0, NULL, TRUE);	
+			
 
 		// Good, look at the command now.
 		if ( (len == sizeof(cmd1) && memcmp(receivedCmd, cmd1, len) == 0)
@@ -410,14 +457,14 @@ void SimulateIso14443bTag(void)
 			// And print whether the CRC fails, just for good measure
 			uint8_t b1, b2;
 			if (len >= 3){ // if crc exists
-			ComputeCrc14443(CRC_14443_B, receivedCmd, len-2, &b1, &b2);
-			if(b1 != receivedCmd[len-2] || b2 != receivedCmd[len-1]) {
-				// Not so good, try again.
-				DbpString("+++CRC fail");
-		
-			} else {
-				DbpString("CRC passes");
-			}
+				ComputeCrc14443(CRC_14443_B, receivedCmd, len-2, &b1, &b2);
+				if(b1 != receivedCmd[len-2] || b2 != receivedCmd[len-1]) {
+					// Not so good, try again.
+					DbpString("+++CRC fail");
+			
+				} else {
+					DbpString("CRC passes");
+				}
 			}
 			//get rid of compiler warning
 			respCodeLen = 0;
@@ -444,41 +491,30 @@ void SimulateIso14443bTag(void)
 		AT91C_BASE_SSC->SSC_THR = 0xff;
 		FpgaSetupSsc();
 
-		uint8_t c;
-	 	// clear receiving shift register and holding register
-		while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));
-		c = AT91C_BASE_SSC->SSC_RHR; (void) c;
-		while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));
-		c = AT91C_BASE_SSC->SSC_RHR; (void) c;
-		
-		// Clear TXRDY:
-		AT91C_BASE_SSC->SSC_THR = 0x00;
-		
 		// Transmit the response.
-		uint16_t FpgaSendQueueDelay = 0;
 		uint16_t i = 0;
-		for(;i < respCodeLen; ) {
-			if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-				AT91C_BASE_SSC->SSC_THR = respCode[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;
-		for (i = 0; i <= fpga_queued_bits/8 + 1; ) {
+		for(;;) {
 			if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-				AT91C_BASE_SSC->SSC_THR = 0x00;
-				FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+				uint8_t b = respCode[i];
+
+				AT91C_BASE_SSC->SSC_THR = b;
+
 				i++;
+				if(i > respCodeLen) {
+					break;
+				}
+			}
+			if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
+				volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+				(void)b;
 			}
 		}
 		
 		// trace the response:
-		if (tracing) LogTrace(resp, respLen, 0, 0, parity, FALSE);			
+		if (tracing)
+			//LogTrace(resp, respLen, 0, 0, parity, FALSE);
+			LogTrace(resp, respLen, 0, 0, NULL, FALSE);
 	}
-	FpgaDisableSscDma();
 }
 
 //=============================================================================
@@ -488,29 +524,6 @@ void SimulateIso14443bTag(void)
 // PC side.
 //=============================================================================
 
-static struct {
-	enum {
-		DEMOD_UNSYNCD,
-		DEMOD_PHASE_REF_TRAINING,
-		DEMOD_AWAITING_FALLING_EDGE_OF_SOF,
-		DEMOD_GOT_FALLING_EDGE_OF_SOF,
-		DEMOD_AWAITING_START_BIT,
-		DEMOD_RECEIVING_DATA
-	}       state;
-	int     bitCount;
-	int     posCount;
-	int     thisBit;
-/* this had been used to add RSSI (Received Signal Strength Indication) to traces. Currently not implemented.
-	int     metric;
-	int     metricN;
-*/
-	uint16_t    shiftReg;
-	uint8_t   *output;
-	int     len;
-	int     sumI;
-	int     sumQ;
-} Demod;
-
 /*
  * Handles reception of a bit from the tag
  *
@@ -525,10 +538,13 @@ static struct {
  *          false if we are still waiting for some more
  *
  */
+#ifndef SUBCARRIER_DETECT_THRESHOLD
+# define SUBCARRIER_DETECT_THRESHOLD	6
+#endif
+
 static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 {
-	int v;
-
+	int v = 0;
 // The soft decision on the bit uses an estimate of just the
 // quadrant of the reference angle, not the exact angle.
 #define MAKE_SOFT_DECISION() { \
@@ -544,8 +560,6 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 		} \
 	}
 
-#define SUBCARRIER_DETECT_THRESHOLD	8
-
 // Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by abs(ci) + abs(cq)
 /* #define CHECK_FOR_SUBCARRIER() { \
 		v = ci; \
@@ -555,7 +569,7 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 		} else { \
 			v -= cq; \
 		} \
-	}		
+	}
  */
 // Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by max(abs(ci),abs(cq)) + 1/2*min(abs(ci),abs(cq)))
 #define CHECK_FOR_SUBCARRIER() { \
@@ -589,11 +603,15 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 			} \
 		} \
 	}
-	
+
+
 	switch(Demod.state) {
 		case DEMOD_UNSYNCD:
+
 			CHECK_FOR_SUBCARRIER();
-			if(v > SUBCARRIER_DETECT_THRESHOLD) {	// subcarrier detected
+
+			// subcarrier detected
+			if(v > SUBCARRIER_DETECT_THRESHOLD) {
 				Demod.state = DEMOD_PHASE_REF_TRAINING;
 				Demod.sumI = ci;
 				Demod.sumQ = cq;
@@ -602,15 +620,18 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 			break;
 
 		case DEMOD_PHASE_REF_TRAINING:
-			if(Demod.posCount < 10*2) {
+			if(Demod.posCount < 8) {
+
 				CHECK_FOR_SUBCARRIER();
+				
 				if (v > SUBCARRIER_DETECT_THRESHOLD) {
 					// set the reference phase (will code a logic '1') by averaging over 32 1/fs.
 					// note: synchronization time > 80 1/fs
 					Demod.sumI += ci;
 					Demod.sumQ += cq;
-					Demod.posCount++;
-				} else {		// subcarrier lost
+					++Demod.posCount;
+				} else {	
+					// subcarrier lost
 					Demod.state = DEMOD_UNSYNCD;
 				}
 			} else {
@@ -619,37 +640,38 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 			break;
 
 		case DEMOD_AWAITING_FALLING_EDGE_OF_SOF:
+			
 			MAKE_SOFT_DECISION();
+			
+			//Dbprintf("ICE: %d %d %d %d %d", v, Demod.sumI, Demod.sumQ, ci, cq );
 			if(v < 0) {	// logic '0' detected
 				Demod.state = DEMOD_GOT_FALLING_EDGE_OF_SOF;
 				Demod.posCount = 0;	// start of SOF sequence
 			} else {
-				//if(Demod.posCount > 200/4) {	// maximum length of TR1 = 200 1/fs
-				if(Demod.posCount > 25*2) {	// maximum length of TR1 = 200 1/fs
-					Demod.state = DEMOD_UNSYNCD;
-				}
+				// maximum length of TR1 = 200 1/fs
+				if(Demod.posCount > 25*2) Demod.state = DEMOD_UNSYNCD;
 			}
-			Demod.posCount++;
+			++Demod.posCount;
 			break;
 
 		case DEMOD_GOT_FALLING_EDGE_OF_SOF:
-			Demod.posCount++;
+			++Demod.posCount;
+			
 			MAKE_SOFT_DECISION();
+			
 			if(v > 0) {
-				if(Demod.posCount < 10*2) { // low phase of SOF too short (< 9 etu). Note: spec is >= 10, but FPGA tends to "smear" edges
+				// low phase of SOF too short (< 9 etu). Note: spec is >= 10, but FPGA tends to "smear" edges
+				if(Demod.posCount < 9*2) { 
 					Demod.state = DEMOD_UNSYNCD;
 				} else {
 					LED_C_ON(); // Got SOF
 					Demod.state = DEMOD_AWAITING_START_BIT;
 					Demod.posCount = 0;
 					Demod.len = 0;
-/* this had been used to add RSSI (Received Signal Strength Indication) to traces. Currently not implemented.
-					Demod.metricN = 0;
-					Demod.metric = 0;
-*/
 				}
 			} else {
-				if(Demod.posCount > 13*2) { // low phase of SOF too long (> 12 etu)
+				// low phase of SOF too long (> 12 etu)
+				if (Demod.posCount > 12*2) { 
 					Demod.state = DEMOD_UNSYNCD;
 					LED_C_OFF();
 				}
@@ -657,9 +679,11 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 			break;
 
 		case DEMOD_AWAITING_START_BIT:
-			Demod.posCount++;
+			++Demod.posCount;
+			
 			MAKE_SOFT_DECISION();
-			if(v > 0) {
+			
+			if (v > 0) {
 				if(Demod.posCount > 3*2) { 		// max 19us between characters = 16 1/fs, max 3 etu after low phase of SOF = 24 1/fs
 					Demod.state = DEMOD_UNSYNCD;
 					LED_C_OFF();
@@ -674,42 +698,39 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 			break;
 
 		case DEMOD_RECEIVING_DATA:
+			
 			MAKE_SOFT_DECISION();
-			if(Demod.posCount == 0) { 			// first half of bit
+
+			if (Demod.posCount == 0) { 
+				// first half of bit
 				Demod.thisBit = v;
 				Demod.posCount = 1;
-			} else {							// second half of bit
+			} else {
+				// second half of bit
 				Demod.thisBit += v;
-
-/* this had been used to add RSSI (Received Signal Strength Indication) to traces. Currently not implemented.
-				if(Demod.thisBit > 0) {
-					Demod.metric += Demod.thisBit;
-				} else {
-					Demod.metric -= Demod.thisBit;
-				}
-				(Demod.metricN)++;
-*/				
-
 				Demod.shiftReg >>= 1;
-				if(Demod.thisBit > 0) {	// logic '1'
-					Demod.shiftReg |= 0x200;
-				}
 
-				Demod.bitCount++;
+				// logic '1'
+				if(Demod.thisBit > 0)  Demod.shiftReg |= 0x200;
+
+				++Demod.bitCount;
+				
 				if(Demod.bitCount == 10) {
+					
 					uint16_t s = Demod.shiftReg;
-					if((s & 0x200) && !(s & 0x001)) { // stop bit == '1', start bit == '0'
+					
+					// stop bit == '1', start bit == '0'
+					if((s & 0x200) && !(s & 0x001)) { 
 						uint8_t b = (s >> 1);
 						Demod.output[Demod.len] = b;
-						Demod.len++;
+						++Demod.len;
 						Demod.state = DEMOD_AWAITING_START_BIT;
 					} else {
 						Demod.state = DEMOD_UNSYNCD;
 						LED_C_OFF();
-						if(s == 0x000) {
-							// This is EOF (start, stop and all data bits == '0'
-							return TRUE;
-						}
+						
+						// This is EOF (start, stop and all data bits == '0'
+						if(s == 0) return TRUE;
 					}
 				}
 				Demod.posCount = 0;
@@ -725,23 +746,6 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 }
 
 
-static void DemodReset()
-{
-	// Clear out the state of the "UART" that receives from the tag.
-	Demod.len = 0;
-	Demod.state = DEMOD_UNSYNCD;
-	Demod.posCount = 0;
-	memset(Demod.output, 0x00, MAX_FRAME_SIZE);
-}
-
-
-static void DemodInit(uint8_t *data)
-{
-	Demod.output = data;
-	DemodReset();
-}
-
-
 /*
  *  Demodulate the samples we received from the tag, also log to tracebuffer
  *  quiet: set to 'TRUE' to disable debug output
@@ -756,29 +760,24 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
 	// free all previous allocations first
 	BigBuf_free();
 
-	// And put the FPGA in the appropriate mode
-	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
-
 	// The response (tag -> reader) that we're receiving.
-	uint8_t *resp = BigBuf_malloc(MAX_FRAME_SIZE);
-
 	// Set up the demodulator for tag -> reader responses.
-	DemodInit(resp);
+	DemodInit(BigBuf_malloc(MAX_FRAME_SIZE));
 	
 	// The DMA buffer, used to stream samples from the FPGA
 	int8_t *dmaBuf = (int8_t*) BigBuf_malloc(ISO14443B_DMA_BUFFER_SIZE);
 
-
+	// And put the FPGA in the appropriate mode
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
+	
+	// Setup and start DMA.
+	FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE);
+	
 	int8_t *upTo = dmaBuf;
 	lastRxCounter = ISO14443B_DMA_BUFFER_SIZE;
 
 	// Signal field is ON with the appropriate LED:
 	LED_D_ON();
-
-	// Setup and start DMA.
-	FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE);
-
-	
 	for(;;) {
 		int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR;
 		if(behindBy > max) max = behindBy;
@@ -793,30 +792,32 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
 				AT91C_BASE_PDC_SSC->PDC_RNCR = ISO14443B_DMA_BUFFER_SIZE;
 			}
 			lastRxCounter -= 2;
-			if(lastRxCounter <= 0) {
+
+			if(lastRxCounter <= 0)
 				lastRxCounter += ISO14443B_DMA_BUFFER_SIZE;
-			}
 
 			samples += 2;
 
-			if(Handle14443bSamplesDemod(ci | 0x01 , cq | 0x01)) {
-				gotFrame = TRUE;
+			//
+			gotFrame = Handle14443bSamplesDemod(ci , cq );
+			if ( gotFrame )
 				break;
 		}
-	}
 
 		if(samples > n || gotFrame) {
 			break;
 		}
 	}
 
+	//disable
 	AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
 
-	if (!quiet && Demod.len == 0) {
-		Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Demod.len = %d, Demod.sumI = %d, Demod.sumQ = %d",
+	if (!quiet) {
+		Dbprintf("max behindby = %d, samples = %d, gotFrame = %s, Demod.state = %d, Demod.len = %d, Demod.sumI = %d, Demod.sumQ = %d",
 			max,
 			samples, 
-			gotFrame, 
+			(gotFrame) ? "true" : "false", 
+			Demod.state,
 			Demod.len, 
 			Demod.sumI, 
 			Demod.sumQ
@@ -824,10 +825,8 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
 	}
 
 	//Tracing
-	if (tracing && Demod.len > 0) {
-		uint8_t parity[MAX_PARITY_SIZE];
-		LogTrace(Demod.output, Demod.len, 0, 0, parity, FALSE);
-	}
+	if (Demod.len > 0)
+		LogTrace(Demod.output, Demod.len, 0, 0, NULL, FALSE);
 }
 
 
@@ -837,31 +836,25 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
 static void TransmitFor14443b(void)
 {
 	int c;
-
+	volatile uint32_t r;
 	FpgaSetupSsc();
-
-	// Start the timer
-	StartCountSspClk();
 	
-	while(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+	while(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY))
 		AT91C_BASE_SSC->SSC_THR = 0xff;
-	}
 
 	// Signal field is ON with the appropriate Red LED
 	LED_D_ON();
 	// Signal we are transmitting with the Green LED
 	LED_B_ON();
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
-	if ( !PowerOn )
-		SpinDelay(200);
 	
 	for(c = 0; c < 10;) {
 		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
 			AT91C_BASE_SSC->SSC_THR = 0xff;
-			c++;
+			++c;
 		}
 		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-			volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
+			r = AT91C_BASE_SSC->SSC_RHR;
 			(void)r;
 		}
 		WDT_HIT();
@@ -871,13 +864,12 @@ static void TransmitFor14443b(void)
 	for(;;) {
 		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
 			AT91C_BASE_SSC->SSC_THR = ToSend[c];
-			c++;
-			if(c >= ToSendMax) {
+			++c;
+			if(c >= ToSendMax)
 				break;
-			}
 		}
 		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-			volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
+			r = AT91C_BASE_SSC->SSC_RHR;
 			(void)r;
 		}
 		WDT_HIT();
@@ -898,13 +890,12 @@ static void CodeIso14443bAsReader(const uint8_t *cmd, int len)
 	ToSendReset();
 
 	// Establish initial reference level
-	for(i = 0; i < 80; i++) {
+	for(i = 0; i < 40; i++)
 		ToSendStuffBit(1);
-	}
+
 	// Send SOF
-	for(i = 0; i < 11; i++) {
+	for(i = 0; i < 10; i++)
 		ToSendStuffBit(0);
-	}
 
 	for(i = 0; i < len; i++) {
 		// Stop bits/EGT
@@ -915,31 +906,30 @@ static void CodeIso14443bAsReader(const uint8_t *cmd, int len)
 		// Data bits
 		b = cmd[i];
 		for(j = 0; j < 8; j++) {
-			if(b & 1) {
+			if(b & 1)
 				ToSendStuffBit(1);
-			} else {
+			else
 				ToSendStuffBit(0);
-			}
+			
 			b >>= 1;
 		}
 	}
 	// Send EOF
 	ToSendStuffBit(1);
-	for(i = 0; i < 11; i++) {
+	for(i = 0; i < 10; i++)
 		ToSendStuffBit(0);
-	}
-	for(i = 0; i < 8; i++) {
+	
+	for(i = 0; i < 8; i++)
 		ToSendStuffBit(1);
-	}
+
 
 	// And then a little more, to make sure that the last character makes
 	// it out before we switch to rx mode.
-	for(i = 0; i < 10; i++) {
+	for(i = 0; i < 24; i++)
 		ToSendStuffBit(1);
-	}
 
 	// Convert from last character reference to length
-	ToSendMax++;
+	++ToSendMax;
 }
 
 
@@ -951,8 +941,9 @@ static void CodeAndTransmit14443bAsReader(const uint8_t *cmd, int len)
 	CodeIso14443bAsReader(cmd, len);
 	TransmitFor14443b();
 	if (tracing) {
-		uint8_t parity[MAX_PARITY_SIZE];
-		LogTrace(cmd,len, 0, 0, parity, TRUE);
+		//uint8_t parity[MAX_PARITY_SIZE];
+		//LogTrace(cmd,len, 0, 0, parity, TRUE);
+		LogTrace(cmd,len, 0, 0, NULL, TRUE);
 	}
 }
 
@@ -974,17 +965,15 @@ int iso14443b_apdu(uint8_t const *message, size_t message_length, uint8_t *respo
 	// send
 	CodeAndTransmit14443bAsReader(message_frame, message_length + 4);
 	// get response
-	GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT*100, TRUE);
+	GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
 	if(Demod.len < 3)
-	{
 		return 0;
-	}
+	
 	// TODO: Check CRC
 	// copy response contents
 	if(response != NULL)
-	{
 		memcpy(response, Demod.output, Demod.len);
-	}
+
 	return Demod.len;
 }
 
@@ -1007,9 +996,7 @@ int iso14443b_select_card()
 	GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
 	// ATQB too short?
 	if (Demod.len < 14)
-	{
 		return 2;
-	}
 
     // select the tag
     // copy the PUPI to ATTRIB
@@ -1022,9 +1009,8 @@ int iso14443b_select_card()
     GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
     // Answer to ATTRIB too short?
     if(Demod.len < 3)
-	{
 		return 2;
-	}
+	
 	// reset PCB block number
 	pcb_blocknum = 0;
 	return 1;
@@ -1032,22 +1018,26 @@ int iso14443b_select_card()
 
 // Set up ISO 14443 Type B communication (similar to iso14443a_setup)
 void iso14443b_setup() {
+
 	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-	BigBuf_free();
+
+	BigBuf_free(); BigBuf_Clear_ext(false);
+	DemodReset();
+	UartReset();
+	
 	// Set up the synchronous serial port
 	FpgaSetupSsc();
+
 	// connect Demodulated Signal to ADC:
 	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
 
 	// Signal field is on with the appropriate LED
     LED_D_ON();
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
+	SpinDelay(200);
 
 	// Start the timer
 	StartCountSspClk();
-
-	DemodReset();
-	UartReset();
 }
 
 //-----------------------------------------------------------------------------
@@ -1062,8 +1052,6 @@ void iso14443b_setup() {
 void ReadSTMemoryIso14443b(uint32_t dwLast)
 {
 	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-	BigBuf_free();
-
 	clear_trace();
 	set_tracing(TRUE);
 
@@ -1091,6 +1079,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 
 	if (Demod.len == 0) {
 		DbpString("No response from tag");
+		set_tracing(FALSE);	
 		return;
 	} else {
 		Dbprintf("Randomly generated Chip ID (+ 2 byte CRC): %02x %02x %02x",
@@ -1106,17 +1095,20 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 	GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
 	if (Demod.len != 3) {
 		Dbprintf("Expected 3 bytes from tag, got %d", Demod.len);
+		set_tracing(FALSE);	
 		return;
 	}
 	// Check the CRC of the answer:
 	ComputeCrc14443(CRC_14443_B, Demod.output, 1 , &cmd1[2], &cmd1[3]);
 	if(cmd1[2] != Demod.output[1] || cmd1[3] != Demod.output[2]) {
 		DbpString("CRC Error reading select response.");
+		set_tracing(FALSE);	
 		return;
 	}
 	// Check response from the tag: should be the same UID as the command we just sent:
 	if (cmd1[1] != Demod.output[0]) {
 		Dbprintf("Bad response to SELECT from Tag, aborting: %02x %02x", cmd1[1], Demod.output[0]);
+		set_tracing(FALSE);	
 		return;
 	}
 
@@ -1128,6 +1120,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 	GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
 	if (Demod.len != 10) {
 		Dbprintf("Expected 10 bytes from tag, got %d", Demod.len);
+		set_tracing(FALSE);	
 		return;
 	}
 	// The check the CRC of the answer (use cmd1 as temporary variable):
@@ -1175,6 +1168,8 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 		}
 		i++;
 	}
+	
+	set_tracing(FALSE);
 }
 
 
@@ -1203,7 +1198,7 @@ void RAMFUNC SnoopIso14443b(void)
 	int triggered = TRUE;			// TODO: set and evaluate trigger condition
 
 	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-	BigBuf_free();
+	BigBuf_free(); BigBuf_Clear_ext(false);
 
 	clear_trace();
 	set_tracing(TRUE);
@@ -1241,7 +1236,7 @@ void RAMFUNC SnoopIso14443b(void)
 	upTo = dmaBuf;
 	lastRxCounter = ISO14443B_DMA_BUFFER_SIZE;
 	FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE);
-	uint8_t parity[MAX_PARITY_SIZE];
+	//uint8_t parity[MAX_PARITY_SIZE] = {0x00};
 
 	bool TagIsActive = FALSE;
 	bool ReaderIsActive = FALSE;
@@ -1270,10 +1265,12 @@ void RAMFUNC SnoopIso14443b(void)
 				Dbprintf("blew circular buffer! behindBy=%d", behindBy);
 				break;
 			}
+			
 			if(!tracing) {
-				DbpString("Reached trace limit");
+				DbpString("Trace full");
 				break;
 			}
+			
 			if(BUTTON_PRESS()) {
 				DbpString("cancelled");
 				break;
@@ -1283,26 +1280,28 @@ void RAMFUNC SnoopIso14443b(void)
 		samples += 2;
 
 		if (!TagIsActive) {							// no need to try decoding reader data if the tag is sending
-			if(Handle14443bUartBit(ci & 0x01)) {
-			if(triggered && tracing) {
-					LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE);
-			}
-			/* 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();
-		}
-			if(Handle14443bUartBit(cq & 0x01)) {
-			if(triggered && tracing) {
-					LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE);
+			if (Handle14443bUartBit(ci & 0x01)) {
+				if(triggered && tracing) {
+					//LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE);
+					LogTrace(Uart.output, Uart.byteCnt, samples, samples, NULL, TRUE);
+				}
+				/* 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();
 			}
-			/* 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();
-		}
+			if (Handle14443bUartBit(cq & 0x01)) {
+				if(triggered && tracing) {
+					//LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE);
+					LogTrace(Uart.output, Uart.byteCnt, samples, samples, NULL, TRUE);
+				}
+					/* 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();
+				}
 			ReaderIsActive = (Uart.state > STATE_GOT_FALLING_EDGE_OF_SOF);
 		}
 
@@ -1310,24 +1309,23 @@ void RAMFUNC SnoopIso14443b(void)
 			// is this | 0x01 the error?   & 0xfe  in https://github.com/Proxmark/proxmark3/issues/103
 			if(Handle14443bSamplesDemod(ci | 0x01, cq | 0x01)) {
 
-			//Use samples as a time measurement
-			if(tracing)
-			{
-				//uint8_t parity[MAX_PARITY_SIZE];
-				LogTrace(Demod.output, Demod.len, samples, samples, parity, FALSE);
-			}
-			triggered = TRUE;
+				//Use samples as a time measurement
+				if(tracing)
+				    //LogTrace(Demod.output, Demod.len, samples, samples, parity, FALSE);
+					LogTrace(Demod.output, Demod.len, samples, samples, NULL, FALSE);
 
-			// And ready to receive another response.
-			DemodReset();
-		}
+				triggered = TRUE;
+
+				// And ready to receive another response.
+				DemodReset();
+			}
 			TagIsActive = (Demod.state > DEMOD_GOT_FALLING_EDGE_OF_SOF);
 		}
-
 	}
 
 	FpgaDisableSscDma();
 	LEDsoff();
+	
 	AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
 	DbpString("Snoop statistics:");
 	Dbprintf("  Max behind by: %i", maxBehindBy);
@@ -1335,6 +1333,7 @@ void RAMFUNC SnoopIso14443b(void)
 	Dbprintf("  Uart ByteCnt: %i", Uart.byteCnt);
 	Dbprintf("  Uart ByteCntMax: %i", Uart.byteCntMax);
 	Dbprintf("  Trace length: %i", BigBuf_get_traceLen());
+	set_tracing(FALSE);	
 }
 
 
@@ -1352,38 +1351,32 @@ void RAMFUNC SnoopIso14443b(void)
  */
 void SendRawCommand14443B(uint32_t datalen, uint32_t recv, uint8_t powerfield, uint8_t data[])
 {
+	// param ISO_
+	// param ISO_CONNECT
+	// param ISO14A_NO_DISCONNECT
+	//if (param & ISO14A_NO_DISCONNECT)
+	// return;
 	iso14443b_setup();
-	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-	BigBuf_free();
-	if ( !PowerOn ){
-		FpgaSetupSsc();
-	}
-	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-	
-	// Start the timer
-	StartCountSspClk();
-
-	DemodReset();
-	UartReset();
 	
 	if ( datalen == 0 && recv == 0 && powerfield == 0){
+		
+	} else {		
 		clear_trace();
-	} else {
 		set_tracing(TRUE);
 		CodeAndTransmit14443bAsReader(data, datalen);
 	}
 
-	if(recv) {
+	if (recv) {
 		GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, FALSE);
-		uint16_t iLen = MIN(Demod.len, USB_CMD_DATA_SIZE);
-		cmd_send(CMD_ACK, iLen, 0, 0, Demod.output, iLen);
+		uint16_t len = MIN(Demod.len, USB_CMD_DATA_SIZE);
+		cmd_send(CMD_ACK, len, 0, 0, Demod.output, len);
 	}
 	
-	if(!powerfield) {
+	if (!powerfield) {
 		FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
 		FpgaDisableSscDma();
+		set_tracing(FALSE);
 		LED_D_OFF();
-		PowerOn = 0;
 	}
 }