// Jonathan Westhues, split Nov 2006
// Modified by Greg Jones, Jan 2009
// Modified by Adrian Dabrowski "atrox", Mar-Sept 2010,Oct 2011
+// Modified by piwi, Oct 2018
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// Routines to support ISO 15693. This includes both the reader software and
-// the `fake tag' modes, but at the moment I've implemented only the reader
-// stuff, and that barely.
-// Modified to perform modulation onboard in arm rather than on PC
-// Also added additional reader commands (SELECT, READ etc.)
+// the `fake tag' modes.
//-----------------------------------------------------------------------------
-// The ISO 15693 describes two transmission modes from reader to tag, and 4
-// transmission modes from tag to reader. As of Mar 2010 this code only
-// supports one of each: "1of4" mode from reader to tag, and the highspeed
-// variant with one subcarrier from card to reader.
-// As long, as the card fully support ISO 15693 this is no problem, since the
-// reader chooses both data rates, but some non-standard tags do not. Further for
-// the simulation to work, we will need to support all data rates.
+
+// The ISO 15693 describes two transmission modes from reader to tag, and four
+// transmission modes from tag to reader. As of Oct 2018 this code supports
+// both reader modes and the high speed variant with one subcarrier from card to reader.
+// As long as the card fully support ISO 15693 this is no problem, since the
+// reader chooses both data rates, but some non-standard tags do not.
+// For card simulation, the code supports both high and low speed modes with one subcarrier.
//
// VCD (reader) -> VICC (tag)
// 1 out of 256:
-// data rate: 1,66 kbit/s (fc/8192)
+// data rate: 1,66 kbit/s (fc/8192)
// used for long range
// 1 out of 4:
// data rate: 26,48 kbit/s (fc/512)
// used for short range, high speed
-//
+//
// VICC (tag) -> VCD (reader)
// Modulation:
// ASK / one subcarrier (423,75 khz)
// high ASK: 26,48 kbit/s
// high FSK: 26,69 kbit/s
//-----------------------------------------------------------------------------
-// added "1 out of 256" mode (for VCD->PICC) - atrox 20100911
// Random Remarks:
// *) UID is always used "transmission order" (LSB), which is reverse to display order
// TODO / BUGS / ISSUES:
-// *) writing to tags takes longer: we miss the answer from the tag in most cases
-// -> tweak the read-timeout times
-// *) signal decoding from the card is still a bit shaky.
-// *) signal decoding is unable to detect collissions.
-// *) add anti-collission support for inventory-commands
+// *) signal decoding is unable to detect collisions.
+// *) add anti-collision support for inventory-commands
// *) read security status of a block
-// *) sniffing and simulation do only support one transmission mode. need to support
-// all 8 transmission combinations
-// *) remove or refactor code under "depricated"
+// *) sniffing and simulation do not support two subcarrier modes.
+// *) remove or refactor code under "depricated"
// *) document all the functions
#include "apps.h"
#include "string.h"
#include "iso15693tools.h"
+#include "protocols.h"
#include "cmd.h"
#define arraylen(x) (sizeof(x)/sizeof((x)[0]))
+static int DEBUG = 0;
+
///////////////////////////////////////////////////////////////////////
// ISO 15693 Part 2 - Air Interface
// This section basicly contains transmission and receiving of bits
#define AddCrc(data,datalen) Iso15693AddCrc(data,datalen)
#define sprintUID(target,uid) Iso15693sprintUID(target,uid)
-// approximate amplitude=sqrt(ci^2+cq^2)
-#define AMPLITUDE(ci, cq) (MAX(ABS(ci), ABS(cq)) + (MIN(ABS(ci), ABS(cq))>>1))
+// approximate amplitude=sqrt(ci^2+cq^2) by amplitude = max(|ci|,|cq|) + 1/2*min(|ci|,|cq|)
+#define AMPLITUDE(ci, cq) (MAX(ABS(ci), ABS(cq)) + MIN(ABS(ci), ABS(cq))/2)
-static int DEBUG = 0;
+// buffers
+#define ISO15693_DMA_BUFFER_SIZE 128
+#define ISO15693_MAX_RESPONSE_LENGTH 36 // allows read single block with the maximum block size of 256bits. Read multiple blocks not supported yet
+#define ISO15693_MAX_COMMAND_LENGTH 45 // allows write single block with the maximum block size of 256bits. Write multiple blocks not supported yet
+// timing. Delays in SSP_CLK ticks.
+#define DELAY_READER_TO_ARM 8
+#define DELAY_ARM_TO_READER 1
+#define DELAY_ISO15693_VCD_TO_VICC 132 // 132/423.75kHz = 311.5us from end of EOF to start of tag response
// ---------------------------
-// Signal Processing
+// Signal Processing
// ---------------------------
// prepare data using "1 out of 4" code for later transmission
-// resulting data rate is 26,48 kbit/s (fc/512)
+// resulting data rate is 26.48 kbit/s (fc/512)
// cmd ... data
// n ... length of data
static void CodeIso15693AsReader(uint8_t *cmd, int n)
ToSendStuffBit(0);
ToSendStuffBit(1);
- // And slack at the end, too.
- for(i = 0; i < 24; i++) {
+ // Fill remainder of last byte with 1
+ for(i = 0; i < 4; i++) {
ToSendStuffBit(1);
}
}
-// encode data using "1 out of 256" sheme
-// data rate is 1,66 kbit/s (fc/8192)
+// encode data using "1 out of 256" scheme
+// data rate is 1,66 kbit/s (fc/8192)
// is designed for more robust communication over longer distances
static void CodeIso15693AsReader256(uint8_t *cmd, int n)
{
ToSendStuffBit(1);
ToSendStuffBit(1);
ToSendStuffBit(0);
-
+
for(i = 0; i < n; i++) {
for (j = 0; j<=255; j++) {
if (cmd[i]==j) {
} else {
ToSendStuffBit(1);
ToSendStuffBit(1);
- }
- }
+ }
+ }
}
// EOF
ToSendStuffBit(1);
ToSendStuffBit(0);
ToSendStuffBit(1);
- // And slack at the end, too.
- for(i = 0; i < 24; i++) {
+ // Fill remainder of last byte with 1
+ for(i = 0; i < 4; i++) {
ToSendStuffBit(1);
}
+
+ ToSendMax++;
}
-// Transmit the command (to the tag) that was placed in ToSend[].
-static void TransmitTo15693Tag(const uint8_t *cmd, int len, int *samples, int *wait)
+static void CodeIso15693AsTag(uint8_t *cmd, int n)
{
- int c;
+ ToSendReset();
+
+ // SOF
+ ToSendStuffBit(0);
+ ToSendStuffBit(0);
+ ToSendStuffBit(0);
+ ToSendStuffBit(1);
+ ToSendStuffBit(1);
+ ToSendStuffBit(1);
+ ToSendStuffBit(0);
+ ToSendStuffBit(1);
+
+ // data
+ for(int i = 0; i < n; i++) {
+ for(int j = 0; j < 8; j++) {
+ if ((cmd[i] >> j) & 0x01) {
+ ToSendStuffBit(0);
+ ToSendStuffBit(1);
+ } else {
+ ToSendStuffBit(1);
+ ToSendStuffBit(0);
+ }
+ }
+ }
+
+ // EOF
+ ToSendStuffBit(1);
+ ToSendStuffBit(0);
+ ToSendStuffBit(1);
+ ToSendStuffBit(1);
+ ToSendStuffBit(1);
+ ToSendStuffBit(0);
+ ToSendStuffBit(0);
+ ToSendStuffBit(0);
-// FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_ISO14443A | FPGA_HF_ISO14443A_READER_MOD);
+ ToSendMax++;
+}
+
+
+// Transmit the command (to the tag) that was placed in cmd[].
+static void TransmitTo15693Tag(const uint8_t *cmd, int len)
+{
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_TX);
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX);
- if(*wait < 10) { *wait = 10; }
-
-// 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(;;) {
+
+ LED_B_ON();
+ for(int c = 0; c < len; ) {
if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
- AT91C_BASE_SSC->SSC_THR = cmd[c];
+ 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();
}
- *samples = (c + *wait) << 3;
+ LED_B_OFF();
}
//-----------------------------------------------------------------------------
-// Transmit the command (to the reader) that was placed in ToSend[].
+// Transmit the tag response (to the reader) that was placed in cmd[].
//-----------------------------------------------------------------------------
-static void TransmitTo15693Reader(const uint8_t *cmd, int len, int *samples, int *wait)
+static void TransmitTo15693Reader(const uint8_t *cmd, size_t len, uint32_t start_time, bool slow)
{
- int c = 0;
- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR|FPGA_HF_SIMULATOR_MODULATE_424K);
- if(*wait < 10) { *wait = 10; }
+ // don't use the FPGA_HF_SIMULATOR_MODULATE_424K_8BIT minor mode. It would spoil GetCountSspClk()
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_424K);
- 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;
+ uint8_t shift_delay = start_time & 0x00000007;
+ uint8_t bitmask = 0x00;
+ for (int i = 0; i < shift_delay; i++) {
+ bitmask |= (0x01 << i);
+ }
+
+ while (GetCountSspClk() < (start_time & 0xfffffff8)) ;
+ AT91C_BASE_SSC->SSC_THR = 0x00; // clear TXRDY
+
+ LED_C_ON();
+ uint8_t bits_to_shift = 0x00;
+ for(size_t c = 0; c <= len; c++) {
+ uint8_t bits_to_send = bits_to_shift << (8 - shift_delay) | (c==len?0x00:cmd[c]) >> shift_delay;
+ bits_to_shift = cmd[c] & bitmask;
+ for (int i = 7; i >= 0; i--) {
+ for (int j = 0; j < (slow?4:1); ) {
+ if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
+ if (bits_to_send >> i & 0x01) {
+ AT91C_BASE_SSC->SSC_THR = 0xff;
+ } else {
+ AT91C_BASE_SSC->SSC_THR = 0x00;
+ }
+ j++;
+ }
+ WDT_HIT();
+ }
}
- WDT_HIT();
}
- *samples = (c + *wait) << 3;
+ LED_C_OFF();
}
-// Read from Tag
-// Parameters:
-// receivedResponse
-// maxLen
-// samples
-// elapsed
-// returns:
-// number of decoded bytes
-static int GetIso15693AnswerFromTag(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed)
+//=============================================================================
+// An ISO 15693 decoder for tag responses (one subcarrier only).
+// Uses cross correlation to identify the SOF, each bit, and EOF.
+// This function is called 8 times per bit (every 2 subcarrier cycles).
+// Subcarrier frequency fs is 424kHz, 1/fs = 2,36us,
+// i.e. function is called every 4,72us
+// LED handling:
+// LED C -> ON once we have received the SOF and are expecting the rest.
+// LED C -> OFF once we have received EOF or are unsynced
+//
+// Returns: true if we received a EOF
+// false if we are still waiting for some more
+//=============================================================================
+
+#define SUBCARRIER_DETECT_THRESHOLD 2
+#define SOF_CORRELATOR_LEN (1<<5)
+
+typedef struct DecodeTag {
+ enum {
+ STATE_TAG_UNSYNCD,
+ STATE_TAG_AWAIT_SOF_1,
+ STATE_TAG_AWAIT_SOF_2,
+ STATE_TAG_RECEIVING_DATA,
+ STATE_TAG_AWAIT_EOF
+ } state;
+ int bitCount;
+ int posCount;
+ enum {
+ LOGIC0,
+ LOGIC1,
+ SOF_PART1,
+ SOF_PART2
+ } lastBit;
+ uint16_t shiftReg;
+ uint8_t *output;
+ int len;
+ int sum1, sum2;
+ uint8_t SOF_low;
+ uint8_t SOF_high;
+ uint8_t SOF_last;
+ int32_t SOF_corr;
+ int32_t SOF_corr_prev;
+ uint8_t SOF_correlator[SOF_CORRELATOR_LEN];
+} DecodeTag_t;
+
+static int Handle15693SamplesFromTag(int8_t ci, int8_t cq, DecodeTag_t *DecodeTag)
{
- int c = 0;
- uint8_t *dest = BigBuf_get_addr();
- int getNext = 0;
+ switch(DecodeTag->state) {
+ case STATE_TAG_UNSYNCD:
+ // initialize SOF correlator. We are looking for 12 samples low and 12 samples high.
+ DecodeTag->SOF_low = 0;
+ DecodeTag->SOF_high = 12;
+ DecodeTag->SOF_last = 23;
+ memset(DecodeTag->SOF_correlator, 0x00, DecodeTag->SOF_last + 1);
+ DecodeTag->SOF_correlator[DecodeTag->SOF_last] = AMPLITUDE(ci,cq);
+ DecodeTag->SOF_corr = DecodeTag->SOF_correlator[DecodeTag->SOF_last];
+ DecodeTag->SOF_corr_prev = DecodeTag->SOF_corr;
+ // initialize Decoder
+ DecodeTag->posCount = 0;
+ DecodeTag->bitCount = 0;
+ DecodeTag->len = 0;
+ DecodeTag->state = STATE_TAG_AWAIT_SOF_1;
+ break;
+
+ case STATE_TAG_AWAIT_SOF_1:
+ // calculate the correlation in real time. Look at differences only.
+ DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_low++];
+ DecodeTag->SOF_corr -= 2*DecodeTag->SOF_correlator[DecodeTag->SOF_high++];
+ DecodeTag->SOF_last++;
+ DecodeTag->SOF_low &= (SOF_CORRELATOR_LEN-1);
+ DecodeTag->SOF_high &= (SOF_CORRELATOR_LEN-1);
+ DecodeTag->SOF_last &= (SOF_CORRELATOR_LEN-1);
+ DecodeTag->SOF_correlator[DecodeTag->SOF_last] = AMPLITUDE(ci,cq);
+ DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_last];
+
+ // if correlation increases for 10 consecutive samples, we are close to maximum correlation
+ if (DecodeTag->SOF_corr > DecodeTag->SOF_corr_prev + SUBCARRIER_DETECT_THRESHOLD) {
+ DecodeTag->posCount++;
+ } else {
+ DecodeTag->posCount = 0;
+ }
- int8_t prev = 0;
+ if (DecodeTag->posCount == 10) { // correlation increased 10 times
+ DecodeTag->state = STATE_TAG_AWAIT_SOF_2;
+ }
-// NOW READ RESPONSE
- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
- c = 0;
- getNext = false;
- for(;;) {
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
- int8_t b;
- b = (int8_t)AT91C_BASE_SSC->SSC_RHR;
+ DecodeTag->SOF_corr_prev = DecodeTag->SOF_corr;
- // The samples are correlations against I and Q versions of the
- // tone that the tag AM-modulates, so every other sample is I,
- // every other is Q. We just want power, so abs(I) + abs(Q) is
- // close to what we want.
- if(getNext) {
- uint8_t r = AMPLITUDE(b, prev);
+ break;
- dest[c++] = r;
+ case STATE_TAG_AWAIT_SOF_2:
+ // calculate the correlation in real time. Look at differences only.
+ DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_low++];
+ DecodeTag->SOF_corr -= 2*DecodeTag->SOF_correlator[DecodeTag->SOF_high++];
+ DecodeTag->SOF_last++;
+ DecodeTag->SOF_low &= (SOF_CORRELATOR_LEN-1);
+ DecodeTag->SOF_high &= (SOF_CORRELATOR_LEN-1);
+ DecodeTag->SOF_last &= (SOF_CORRELATOR_LEN-1);
+ DecodeTag->SOF_correlator[DecodeTag->SOF_last] = AMPLITUDE(ci,cq);
+ DecodeTag->SOF_corr += DecodeTag->SOF_correlator[DecodeTag->SOF_last];
- if(c >= 4000) {
- break;
+ if (DecodeTag->SOF_corr >= DecodeTag->SOF_corr_prev) { // we are looking for the maximum correlation
+ DecodeTag->SOF_corr_prev = DecodeTag->SOF_corr;
+ } else {
+ DecodeTag->lastBit = SOF_PART1; // detected 1st part of SOF
+ DecodeTag->sum1 = DecodeTag->SOF_correlator[DecodeTag->SOF_last];
+ DecodeTag->sum2 = 0;
+ DecodeTag->posCount = 2;
+ DecodeTag->state = STATE_TAG_RECEIVING_DATA;
+ LED_C_ON();
+ }
+
+ break;
+
+ case STATE_TAG_RECEIVING_DATA:
+ if (DecodeTag->posCount == 1) {
+ DecodeTag->sum1 = 0;
+ DecodeTag->sum2 = 0;
+ }
+
+ if (DecodeTag->posCount <= 4) {
+ DecodeTag->sum1 += AMPLITUDE(ci, cq);
+ } else {
+ DecodeTag->sum2 += AMPLITUDE(ci, cq);
+ }
+
+ if (DecodeTag->posCount == 8) {
+ int16_t corr_1 = (DecodeTag->sum2 - DecodeTag->sum1) / 4;
+ int16_t corr_0 = (DecodeTag->sum1 - DecodeTag->sum2) / 4;
+ int16_t corr_EOF = (DecodeTag->sum1 + DecodeTag->sum2) / 8;
+ if (corr_EOF > corr_0 && corr_EOF > corr_1) {
+ DecodeTag->state = STATE_TAG_AWAIT_EOF;
+ } else if (corr_1 > corr_0) {
+ // logic 1
+ if (DecodeTag->lastBit == SOF_PART1) { // still part of SOF
+ DecodeTag->lastBit = SOF_PART2;
+ } else {
+ DecodeTag->lastBit = LOGIC1;
+ DecodeTag->shiftReg >>= 1;
+ DecodeTag->shiftReg |= 0x80;
+ DecodeTag->bitCount++;
+ if (DecodeTag->bitCount == 8) {
+ DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg;
+ DecodeTag->len++;
+ DecodeTag->bitCount = 0;
+ DecodeTag->shiftReg = 0;
+ }
+ }
+ } else {
+ // logic 0
+ if (DecodeTag->lastBit == SOF_PART1) { // incomplete SOF
+ DecodeTag->state = STATE_TAG_UNSYNCD;
+ LED_C_OFF();
+ } else {
+ DecodeTag->lastBit = LOGIC0;
+ DecodeTag->shiftReg >>= 1;
+ DecodeTag->bitCount++;
+ if (DecodeTag->bitCount == 8) {
+ DecodeTag->output[DecodeTag->len] = DecodeTag->shiftReg;
+ DecodeTag->len++;
+ DecodeTag->bitCount = 0;
+ DecodeTag->shiftReg = 0;
+ }
+ }
}
+ DecodeTag->posCount = 0;
+ }
+ DecodeTag->posCount++;
+ break;
+
+ case STATE_TAG_AWAIT_EOF:
+ if (DecodeTag->lastBit == LOGIC0) { // this was already part of EOF
+ LED_C_OFF();
+ return true;
} else {
- prev = b;
+ DecodeTag->state = STATE_TAG_UNSYNCD;
+ LED_C_OFF();
}
+ break;
- getNext = !getNext;
- }
+ default:
+ DecodeTag->state = STATE_TAG_UNSYNCD;
+ LED_C_OFF();
+ break;
}
- //////////////////////////////////////////
- /////////// DEMODULATE ///////////////////
- //////////////////////////////////////////
+ return false;
+}
- int i, j;
- int max = 0, maxPos=0;
- int skip = 2;
+static void DecodeTagInit(DecodeTag_t *DecodeTag, uint8_t *data)
+{
+ DecodeTag->output = data;
+ DecodeTag->state = STATE_TAG_UNSYNCD;
+}
+
+/*
+ * Receive and decode the tag response, also log to tracebuffer
+ */
+static int GetIso15693AnswerFromTag(uint8_t* response, int timeout)
+{
+ int maxBehindBy = 0;
+ int lastRxCounter, samples = 0;
+ int8_t ci, cq;
+ bool gotFrame = false;
+
+ uint16_t dmaBuf[ISO15693_DMA_BUFFER_SIZE];
+
+ // the Decoder data structure
+ DecodeTag_t DecodeTag;
+ DecodeTagInit(&DecodeTag, response);
+
+ // wait for last transfer to complete
+ while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY));
+
+ // And put the FPGA in the appropriate mode
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
+
+ // Setup and start DMA.
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
+ FpgaSetupSscDma((uint8_t*) dmaBuf, ISO15693_DMA_BUFFER_SIZE);
+ uint16_t *upTo = dmaBuf;
+ lastRxCounter = ISO15693_DMA_BUFFER_SIZE;
+
+ for(;;) {
+ int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO15693_DMA_BUFFER_SIZE-1);
+ if(behindBy > maxBehindBy) {
+ maxBehindBy = behindBy;
+ }
+
+ if (behindBy < 1) continue;
+
+ ci = (int8_t)(*upTo >> 8);
+ cq = (int8_t)(*upTo & 0xff);
- // First, correlate for SOF
- for(i = 0; i < 200; i++) { // usually, SOF is found around i = 60
- int corr = 0;
- for(j = 0; j < arraylen(FrameSOF); j += skip) {
- corr += FrameSOF[j]*dest[i+(j/skip)];
+ upTo++;
+ lastRxCounter--;
+ if(upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content.
+ upTo = dmaBuf; // start reading the circular buffer from the beginning
+ lastRxCounter += ISO15693_DMA_BUFFER_SIZE;
}
- if(corr > max) {
- max = corr;
- maxPos = i;
+ if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_ENDRX)) { // DMA Counter Register had reached 0, already rotated.
+ AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf; // refresh the DMA Next Buffer and
+ AT91C_BASE_PDC_SSC->PDC_RNCR = ISO15693_DMA_BUFFER_SIZE; // DMA Next Counter registers
}
+ samples++;
+
+ if (Handle15693SamplesFromTag(ci, cq, &DecodeTag)) {
+ gotFrame = true;
+ break;
+ }
+
+ if(samples > timeout && DecodeTag.state < STATE_TAG_RECEIVING_DATA) {
+ DecodeTag.len = 0;
+ break;
+ }
+
}
- if (DEBUG) Dbprintf("SOF at %d, correlation %d", maxPos, max/(arraylen(FrameSOF)/skip));
- int k = 0; // this will be our return value
+ FpgaDisableSscDma();
- // greg - If correlation is less than 1 then there's little point in continuing
- if ((max/(arraylen(FrameSOF)/skip)) >= 1)
- {
+ if (DEBUG) Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Decoder: state = %d, len = %d, bitCount = %d, posCount = %d",
+ maxBehindBy, samples, gotFrame, DecodeTag.state, DecodeTag.len, DecodeTag.bitCount, DecodeTag.posCount);
+
+ if (tracing && DecodeTag.len > 0) {
+ LogTrace(DecodeTag.output, DecodeTag.len, 0, 0, NULL, false);
+ }
+
+ return DecodeTag.len;
+}
- i = maxPos + arraylen(FrameSOF)/skip;
-
- uint8_t outBuf[20];
- memset(outBuf, 0, sizeof(outBuf));
- uint8_t mask = 0x01;
- for(;;) {
- int corr0 = 0, corr00 = 0, corr01 = 0, corr1 = 0, corrEOF = 0;
- for(j = 0; j < arraylen(Logic0); j += skip) {
- corr0 += Logic0[j]*dest[i+(j/skip)];
+
+//=============================================================================
+// An ISO15693 decoder for reader commands.
+//
+// This function is called 4 times per bit (every 2 subcarrier cycles).
+// Subcarrier frequency fs is 848kHz, 1/fs = 1,18us, i.e. function is called every 2,36us
+// LED handling:
+// LED B -> ON once we have received the SOF and are expecting the rest.
+// LED B -> OFF once we have received EOF or are in error state or unsynced
+//
+// Returns: true if we received a EOF
+// false if we are still waiting for some more
+//=============================================================================
+
+typedef struct DecodeReader {
+ enum {
+ STATE_READER_UNSYNCD,
+ STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF,
+ STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF,
+ STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF,
+ STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4,
+ STATE_READER_RECEIVE_DATA_1_OUT_OF_4,
+ STATE_READER_RECEIVE_DATA_1_OUT_OF_256
+ } state;
+ enum {
+ CODING_1_OUT_OF_4,
+ CODING_1_OUT_OF_256
+ } Coding;
+ uint8_t shiftReg;
+ uint8_t bitCount;
+ int byteCount;
+ int byteCountMax;
+ int posCount;
+ int sum1, sum2;
+ uint8_t *output;
+} DecodeReader_t;
+
+
+static int Handle15693SampleFromReader(uint8_t bit, DecodeReader_t* DecodeReader)
+{
+ switch(DecodeReader->state) {
+ case STATE_READER_UNSYNCD:
+ if(!bit) {
+ // we went low, so this could be the beginning of a SOF
+ DecodeReader->state = STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF;
+ DecodeReader->posCount = 1;
}
- corr01 = corr00 = corr0;
- for(j = 0; j < arraylen(Logic0); j += skip) {
- corr00 += Logic0[j]*dest[i+arraylen(Logic0)/skip+(j/skip)];
- corr01 += Logic1[j]*dest[i+arraylen(Logic0)/skip+(j/skip)];
+ break;
+
+ case STATE_READER_AWAIT_1ST_RISING_EDGE_OF_SOF:
+ DecodeReader->posCount++;
+ if(bit) { // detected rising edge
+ if(DecodeReader->posCount < 4) { // rising edge too early (nominally expected at 5)
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ } else { // SOF
+ DecodeReader->state = STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF;
+ }
+ } else {
+ if(DecodeReader->posCount > 5) { // stayed low for too long
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ } else {
+ // do nothing, keep waiting
+ }
+ }
+ break;
+
+ case STATE_READER_AWAIT_2ND_FALLING_EDGE_OF_SOF:
+ DecodeReader->posCount++;
+ if(!bit) { // detected a falling edge
+ if (DecodeReader->posCount < 20) { // falling edge too early (nominally expected at 21 earliest)
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ } else if (DecodeReader->posCount < 23) { // SOF for 1 out of 4 coding
+ DecodeReader->Coding = CODING_1_OUT_OF_4;
+ DecodeReader->state = STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF;
+ } else if (DecodeReader->posCount < 28) { // falling edge too early (nominally expected at 29 latest)
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ } else { // SOF for 1 out of 4 coding
+ DecodeReader->Coding = CODING_1_OUT_OF_256;
+ DecodeReader->state = STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF;
+ }
+ } else {
+ if(DecodeReader->posCount > 29) { // stayed high for too long
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ } else {
+ // do nothing, keep waiting
+ }
}
- for(j = 0; j < arraylen(Logic1); j += skip) {
- corr1 += Logic1[j]*dest[i+(j/skip)];
+ break;
+
+ case STATE_READER_AWAIT_2ND_RISING_EDGE_OF_SOF:
+ DecodeReader->posCount++;
+ if (bit) { // detected rising edge
+ if (DecodeReader->Coding == CODING_1_OUT_OF_256) {
+ if (DecodeReader->posCount < 32) { // rising edge too early (nominally expected at 33)
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ } else {
+ DecodeReader->posCount = 1;
+ DecodeReader->bitCount = 0;
+ DecodeReader->byteCount = 0;
+ DecodeReader->sum1 = 1;
+ DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_256;
+ LED_B_ON();
+ }
+ } else { // CODING_1_OUT_OF_4
+ if (DecodeReader->posCount < 24) { // rising edge too early (nominally expected at 25)
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ } else {
+ DecodeReader->state = STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4;
+ }
+ }
+ } else {
+ if (DecodeReader->Coding == CODING_1_OUT_OF_256) {
+ if (DecodeReader->posCount > 34) { // signal stayed low for too long
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ } else {
+ // do nothing, keep waiting
+ }
+ } else { // CODING_1_OUT_OF_4
+ if (DecodeReader->posCount > 26) { // signal stayed low for too long
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ } else {
+ // do nothing, keep waiting
+ }
+ }
}
- for(j = 0; j < arraylen(FrameEOF); j += skip) {
- corrEOF += FrameEOF[j]*dest[i+(j/skip)];
+ break;
+
+ case STATE_READER_AWAIT_END_OF_SOF_1_OUT_OF_4:
+ DecodeReader->posCount++;
+ if (bit) {
+ if (DecodeReader->posCount == 33) {
+ DecodeReader->posCount = 1;
+ DecodeReader->bitCount = 0;
+ DecodeReader->byteCount = 0;
+ DecodeReader->sum1 = 1;
+ DecodeReader->state = STATE_READER_RECEIVE_DATA_1_OUT_OF_4;
+ LED_B_ON();
+ } else {
+ // do nothing, keep waiting
+ }
+ } else { // unexpected falling edge
+ DecodeReader->state = STATE_READER_UNSYNCD;
}
- // Even things out by the length of the target waveform.
- corr00 *= 2;
- corr01 *= 2;
- corr0 *= 4;
- corr1 *= 4;
-
- if(corrEOF > corr1 && corrEOF > corr00 && corrEOF > corr01) {
- if (DEBUG) Dbprintf("EOF at %d, correlation %d (corr01: %d, corr00: %d, corr1: %d, corr0: %d)",
- i, corrEOF, corr01, corr00, corr1, corr0);
- break;
- } else if(corr1 > corr0) {
- i += arraylen(Logic1)/skip;
- outBuf[k] |= mask;
+ break;
+
+ case STATE_READER_RECEIVE_DATA_1_OUT_OF_4:
+ DecodeReader->posCount++;
+ if (DecodeReader->posCount == 1) {
+ DecodeReader->sum1 = bit;
+ } else if (DecodeReader->posCount <= 4) {
+ DecodeReader->sum1 += bit;
+ } else if (DecodeReader->posCount == 5) {
+ DecodeReader->sum2 = bit;
} else {
- i += arraylen(Logic0)/skip;
+ DecodeReader->sum2 += bit;
+ }
+ if (DecodeReader->posCount == 8) {
+ DecodeReader->posCount = 0;
+ int corr10 = DecodeReader->sum1 - DecodeReader->sum2;
+ int corr01 = DecodeReader->sum2 - DecodeReader->sum1;
+ int corr11 = (DecodeReader->sum1 + DecodeReader->sum2) / 2;
+ if (corr01 > corr11 && corr01 > corr10) { // EOF
+ LED_B_OFF(); // Finished receiving
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ if (DecodeReader->byteCount != 0) {
+ return true;
+ }
+ }
+ if (corr10 > corr11) { // detected a 2bit position
+ DecodeReader->shiftReg >>= 2;
+ DecodeReader->shiftReg |= (DecodeReader->bitCount << 6);
+ }
+ if (DecodeReader->bitCount == 15) { // we have a full byte
+ DecodeReader->output[DecodeReader->byteCount++] = DecodeReader->shiftReg;
+ if (DecodeReader->byteCount > DecodeReader->byteCountMax) {
+ // buffer overflow, give up
+ LED_B_OFF();
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ }
+ DecodeReader->bitCount = 0;
+ } else {
+ DecodeReader->bitCount++;
+ }
}
- mask <<= 1;
- if(mask == 0) {
- k++;
- mask = 0x01;
+ break;
+
+ case STATE_READER_RECEIVE_DATA_1_OUT_OF_256:
+ DecodeReader->posCount++;
+ if (DecodeReader->posCount == 1) {
+ DecodeReader->sum1 = bit;
+ } else if (DecodeReader->posCount <= 4) {
+ DecodeReader->sum1 += bit;
+ } else if (DecodeReader->posCount == 5) {
+ DecodeReader->sum2 = bit;
+ } else {
+ DecodeReader->sum2 += bit;
}
- if((i+(int)arraylen(FrameEOF)/skip) >= 4000) {
- DbpString("ran off end!");
- break;
+ if (DecodeReader->posCount == 8) {
+ DecodeReader->posCount = 0;
+ int corr10 = DecodeReader->sum1 - DecodeReader->sum2;
+ int corr01 = DecodeReader->sum2 - DecodeReader->sum1;
+ int corr11 = (DecodeReader->sum1 + DecodeReader->sum2) / 2;
+ if (corr01 > corr11 && corr01 > corr10) { // EOF
+ LED_B_OFF(); // Finished receiving
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ if (DecodeReader->byteCount != 0) {
+ return true;
+ }
+ }
+ if (corr10 > corr11) { // detected the bit position
+ DecodeReader->shiftReg = DecodeReader->bitCount;
+ }
+ if (DecodeReader->bitCount == 255) { // we have a full byte
+ DecodeReader->output[DecodeReader->byteCount++] = DecodeReader->shiftReg;
+ if (DecodeReader->byteCount > DecodeReader->byteCountMax) {
+ // buffer overflow, give up
+ LED_B_OFF();
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ }
+ }
+ DecodeReader->bitCount++;
}
- }
- if(mask != 0x01) { // this happens, when we miss the EOF
- // TODO: for some reason this happens quite often
- if (DEBUG) Dbprintf("error, uneven octet! (extra bits!) mask=%02x", mask);
- if (mask<0x08) k--; // discard the last uneven octet;
- // 0x08 is an assumption - but works quite often
- }
- // uint8_t str1 [8];
- // itoa(k,str1);
- // strncat(str1," octets read",8);
-
- // DbpString( str1); // DbpString("%d octets", k);
-
- // for(i = 0; i < k; i+=3) {
- // //DbpString("# %2d: %02x ", i, outBuf[i]);
- // DbpIntegers(outBuf[i],outBuf[i+1],outBuf[i+2]);
- // }
-
- for(i = 0; i < k; i++) {
- receivedResponse[i] = outBuf[i];
- }
- } // "end if correlation > 0" (max/(arraylen(FrameSOF)/skip))
- return k; // return the number of bytes demodulated
+ break;
-/// DbpString("CRC=%04x", Iso15693Crc(outBuf, k-2));
+ default:
+ LED_B_OFF();
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ break;
+ }
+ return false;
}
-// Now the GetISO15693 message from sniffing command
-static int GetIso15693AnswerFromSniff(uint8_t *receivedResponse, int maxLen, int *samples, int *elapsed)
+static void DecodeReaderInit(uint8_t *data, uint16_t max_len, DecodeReader_t* DecodeReader)
{
- int c = 0;
- uint8_t *dest = BigBuf_get_addr();
- int getNext = 0;
+ DecodeReader->output = data;
+ DecodeReader->byteCountMax = max_len;
+ DecodeReader->state = STATE_READER_UNSYNCD;
+ DecodeReader->byteCount = 0;
+ DecodeReader->bitCount = 0;
+ DecodeReader->shiftReg = 0;
+}
- int8_t prev = 0;
-// NOW READ RESPONSE
- FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
- //spindelay(60); // greg - experiment to get rid of some of the 0 byte/failed reads
- c = 0;
- getNext = false;
- for(;;) {
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
- int8_t b = (int8_t)AT91C_BASE_SSC->SSC_RHR;
+//-----------------------------------------------------------------------------
+// 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
+// spinning, waiting for a well-framed command, until either we get one
+// (returns true) or someone presses the pushbutton on the board (false).
+//
+// Assume that we're called with the SSC (to the FPGA) and ADC path set
+// correctly.
+//-----------------------------------------------------------------------------
- // The samples are correlations against I and Q versions of the
- // tone that the tag AM-modulates, so every other sample is I,
- // every other is Q. We just want power, so abs(I) + abs(Q) is
- // close to what we want.
- if(getNext) {
- uint8_t r = AMPLITUDE(b, prev);
+static int GetIso15693CommandFromReader(uint8_t *received, size_t max_len, uint32_t *eof_time)
+{
+ int maxBehindBy = 0;
+ int lastRxCounter, samples = 0;
+ bool gotFrame = false;
+ uint8_t b;
- dest[c++] = r;
+ uint8_t dmaBuf[ISO15693_DMA_BUFFER_SIZE];
- if(c >= BIGBUF_SIZE) {
- break;
- }
- } else {
- prev = b;
- }
+ // the decoder data structure
+ DecodeReader_t DecodeReader;
+ DecodeReaderInit(received, max_len, &DecodeReader);
- getNext = !getNext;
- }
- }
+ // wait for last transfer to complete
+ while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY));
- //////////////////////////////////////////
- /////////// DEMODULATE ///////////////////
- //////////////////////////////////////////
+ LED_D_OFF();
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION);
- int i, j;
- int max = 0, maxPos=0;
+ // clear receive register and wait for next transfer
+ uint32_t temp = AT91C_BASE_SSC->SSC_RHR;
+ (void) temp;
+ while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY)) ;
- int skip = 2;
+ uint32_t bit_time = GetCountSspClk() & 0xfffffff8;
- // First, correlate for SOF
- for(i = 0; i < 38000; i++) {
- int corr = 0;
- for(j = 0; j < arraylen(FrameSOF); j += skip) {
- corr += FrameSOF[j]*dest[i+(j/skip)];
- }
- if(corr > max) {
- max = corr;
- maxPos = i;
+ // Setup and start DMA.
+ FpgaSetupSscDma(dmaBuf, ISO15693_DMA_BUFFER_SIZE);
+ uint8_t *upTo = dmaBuf;
+ lastRxCounter = ISO15693_DMA_BUFFER_SIZE;
+
+ for(;;) {
+ int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO15693_DMA_BUFFER_SIZE-1);
+ if(behindBy > maxBehindBy) {
+ maxBehindBy = behindBy;
}
- }
- if (DEBUG) Dbprintf("SOF at %d, correlation %d", maxPos,max/(arraylen(FrameSOF)/skip));
- int k = 0; // this will be our return value
+ if (behindBy < 1) continue;
- // greg - If correlation is less than 1 then there's little point in continuing
- if ((max/(arraylen(FrameSOF)/skip)) >= 1) // THIS SHOULD BE 1
- {
-
- i = maxPos + arraylen(FrameSOF)/skip;
-
- uint8_t outBuf[20];
- memset(outBuf, 0, sizeof(outBuf));
- uint8_t mask = 0x01;
- for(;;) {
- int corr0 = 0, corr00 = 0, corr01 = 0, corr1 = 0, corrEOF = 0;
- for(j = 0; j < arraylen(Logic0); j += skip) {
- corr0 += Logic0[j]*dest[i+(j/skip)];
- }
- corr01 = corr00 = corr0;
- for(j = 0; j < arraylen(Logic0); j += skip) {
- corr00 += Logic0[j]*dest[i+arraylen(Logic0)/skip+(j/skip)];
- corr01 += Logic1[j]*dest[i+arraylen(Logic0)/skip+(j/skip)];
- }
- for(j = 0; j < arraylen(Logic1); j += skip) {
- corr1 += Logic1[j]*dest[i+(j/skip)];
- }
- for(j = 0; j < arraylen(FrameEOF); j += skip) {
- corrEOF += FrameEOF[j]*dest[i+(j/skip)];
- }
- // Even things out by the length of the target waveform.
- corr00 *= 2;
- corr01 *= 2;
- corr0 *= 4;
- corr1 *= 4;
-
- if(corrEOF > corr1 && corrEOF > corr00 && corrEOF > corr01) {
- if (DEBUG) Dbprintf("EOF at %d, correlation %d (corr01: %d, corr00: %d, corr1: %d, corr0: %d)",
- i, corrEOF, corr01, corr00, corr1, corr0);
- break;
- } else if(corr1 > corr0) {
- i += arraylen(Logic1)/skip;
- outBuf[k] |= mask;
- } else {
- i += arraylen(Logic0)/skip;
- }
- mask <<= 1;
- if(mask == 0) {
- k++;
- mask = 0x01;
- }
- if((i+(int)arraylen(FrameEOF)/skip) >= BIGBUF_SIZE) {
- DbpString("ran off end!");
+ b = *upTo++;
+ lastRxCounter--;
+ if(upTo >= dmaBuf + ISO15693_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content.
+ upTo = dmaBuf; // start reading the circular buffer from the beginning
+ lastRxCounter += ISO15693_DMA_BUFFER_SIZE;
+ }
+ if (AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_ENDRX)) { // DMA Counter Register had reached 0, already rotated.
+ AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf; // refresh the DMA Next Buffer and
+ AT91C_BASE_PDC_SSC->PDC_RNCR = ISO15693_DMA_BUFFER_SIZE; // DMA Next Counter registers
+ }
+
+ for (int i = 7; i >= 0; i--) {
+ if (Handle15693SampleFromReader((b >> i) & 0x01, &DecodeReader)) {
+ *eof_time = bit_time + samples - DELAY_READER_TO_ARM; // end of EOF
+ gotFrame = true;
break;
}
+ samples++;
}
- if(mask != 0x01) {
- DbpString("sniff: error, uneven octet! (discard extra bits!)");
- /// DbpString(" mask=%02x", mask);
+
+ if (gotFrame) {
+ break;
}
- // uint8_t str1 [8];
- // itoa(k,str1);
- // strncat(str1," octets read",8);
-
- // DbpString( str1); // DbpString("%d octets", k);
-
- // for(i = 0; i < k; i+=3) {
- // //DbpString("# %2d: %02x ", i, outBuf[i]);
- // DbpIntegers(outBuf[i],outBuf[i+1],outBuf[i+2]);
- // }
-
- for(i = 0; i < k; i++) {
- receivedResponse[i] = outBuf[i];
+
+ if (BUTTON_PRESS()) {
+ DecodeReader.byteCount = 0;
+ break;
}
- } // "end if correlation > 0" (max/(arraylen(FrameSOF)/skip))
- return k; // return the number of bytes demodulated
-/// DbpString("CRC=%04x", Iso15693Crc(outBuf, k-2));
+ WDT_HIT();
+ }
+
+
+ FpgaDisableSscDma();
+
+ if (DEBUG) Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Decoder: state = %d, len = %d, bitCount = %d, posCount = %d",
+ maxBehindBy, samples, gotFrame, DecodeReader.state, DecodeReader.byteCount, DecodeReader.bitCount, DecodeReader.posCount);
+
+ if (tracing && DecodeReader.byteCount > 0) {
+ LogTrace(DecodeReader.output, DecodeReader.byteCount, 0, 0, NULL, true);
+ }
+
+ return DecodeReader.byteCount;
}
//-----------------------------------------------------------------------------
void AcquireRawAdcSamplesIso15693(void)
{
- uint8_t *dest = BigBuf_get_addr();
+ LEDsoff();
+ LED_A_ON();
- int c = 0;
- int getNext = 0;
- int8_t prev = 0;
+ uint8_t *dest = BigBuf_get_addr();
FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
BuildIdentifyRequest();
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
// Give the tags time to energize
+ LED_D_ON();
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
SpinDelay(100);
// Now send the command
- FpgaSetupSsc();
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_TX);
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX);
- c = 0;
- for(;;) {
+ LED_B_ON();
+ for(int c = 0; c < ToSendMax; ) {
if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
- AT91C_BASE_SSC->SSC_THR = ToSend[c];
+ AT91C_BASE_SSC->SSC_THR = ~ToSend[c];
c++;
- if(c == ToSendMax+3) {
- break;
- }
}
WDT_HIT();
}
+ LED_B_OFF();
+ // wait for last transfer to complete
+ while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY));
+
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
- c = 0;
- getNext = false;
- for(;;) {
+ for(int c = 0; c < 4000; ) {
if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
- int8_t b;
- b = (int8_t)AT91C_BASE_SSC->SSC_RHR;
-
+ uint16_t iq = AT91C_BASE_SSC->SSC_RHR;
// The samples are correlations against I and Q versions of the
- // tone that the tag AM-modulates, so every other sample is I,
- // every other is Q. We just want power, so abs(I) + abs(Q) is
- // close to what we want.
- if(getNext) {
- uint8_t r = AMPLITUDE(b, prev);
-
- dest[c++] = r;
-
- if(c >= 4000) {
- break;
- }
- } else {
- prev = b;
- }
-
- getNext = !getNext;
+ // tone that the tag AM-modulates. We just want power,
+ // so abs(I) + abs(Q) is close to what we want.
+ int8_t i = (int8_t)(iq >> 8);
+ int8_t q = (int8_t)(iq & 0xff);
+ uint8_t r = AMPLITUDE(i, q);
+ dest[c++] = r;
}
}
+
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+ LEDsoff();
}
+// TODO: there is no trigger condition. The 14000 samples represent a time frame of 66ms.
+// It is unlikely that we get something meaningful.
+// TODO: Currently we only record tag answers. Add tracing of reader commands.
+// TODO: would we get something at all? The carrier is switched on...
void RecordRawAdcSamplesIso15693(void)
{
- uint8_t *dest = BigBuf_get_addr();
+ LEDsoff();
+ LED_A_ON();
- int c = 0;
- int getNext = 0;
- int8_t prev = 0;
+ uint8_t *dest = BigBuf_get_addr();
FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
// Setup SSC
- FpgaSetupSsc();
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
// Start from off (no field generated)
- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
- SpinDelay(200);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+ SpinDelay(200);
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
SpinDelay(100);
+ LED_D_ON();
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
- c = 0;
- getNext = false;
- for(;;) {
+ for(int c = 0; c < 14000;) {
if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
- int8_t b;
- b = (int8_t)AT91C_BASE_SSC->SSC_RHR;
-
+ uint16_t iq = AT91C_BASE_SSC->SSC_RHR;
// The samples are correlations against I and Q versions of the
- // tone that the tag AM-modulates, so every other sample is I,
- // every other is Q. We just want power, so abs(I) + abs(Q) is
- // close to what we want.
- if(getNext) {
- uint8_t r = AMPLITUDE(b, prev);
-
- dest[c++] = r;
-
- if(c >= 14000) {
- break;
- }
- } else {
- prev = b;
- }
-
- getNext = !getNext;
- WDT_HIT();
+ // tone that the tag AM-modulates. We just want power,
+ // so abs(I) + abs(Q) is close to what we want.
+ int8_t i = (int8_t)(iq >> 8);
+ int8_t q = (int8_t)(iq & 0xff);
+ uint8_t r = AMPLITUDE(i, q);
+ dest[c++] = r;
}
}
- Dbprintf("fin record");
+
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+ LED_D_OFF();
+ Dbprintf("finished recording");
+ LED_A_OFF();
}
-// Initialize the proxmark as iso15k reader
+// Initialize the proxmark as iso15k reader
// (this might produces glitches that confuse some tags
-void Iso15693InitReader() {
- LED_A_ON();
- LED_B_ON();
- LED_C_OFF();
- LED_D_OFF();
-
+static void Iso15693InitReader() {
FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
// Setup SSC
// FpgaSetupSsc();
// Start from off (no field generated)
+ LED_D_OFF();
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
SpinDelay(10);
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- FpgaSetupSsc();
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
// Give the tags time to energize
+ LED_D_ON();
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
SpinDelay(250);
-
- LED_A_ON();
- LED_B_OFF();
- LED_C_OFF();
- LED_D_OFF();
}
///////////////////////////////////////////////////////////////////////
// ISO 15693 Part 3 - Air Interface
-// This section basicly contains transmission and receiving of bits
+// This section basically contains transmission and receiving of bits
///////////////////////////////////////////////////////////////////////
// Encode (into the ToSend buffers) an identify request, which is the first
// Block number to read
cmd[10] = blockNumber;//0x00;
//Now the CRC
- crc = Crc(cmd, 11); // the crc needs to be calculated over 12 bytes
+ crc = Crc(cmd, 11); // the crc needs to be calculated over 11 bytes
cmd[11] = crc & 0xff;
cmd[12] = crc >> 8;
CodeIso15693AsReader(cmd, sizeof(cmd));
}
+
// Now the VICC>VCD responses when we are simulating a tag
- static void BuildInventoryResponse( uint8_t *uid)
+static void BuildInventoryResponse(uint8_t *uid)
{
uint8_t cmd[12];
uint16_t crc;
- // one sub-carrier, inventory, 1 slot, fast rate
- // AFI is at bit 5 (1<<4) when doing an INVENTORY
- //(1 << 2) | (1 << 5) | (1 << 1);
- cmd[0] = 0; //
+
+ cmd[0] = 0; // No error, no protocol format extension
cmd[1] = 0; // DSFID (data storage format identifier). 0x00 = not supported
// 64-bit UID
cmd[2] = uid[7]; //0x32;
cmd[10] = crc & 0xff;
cmd[11] = crc >> 8;
- CodeIso15693AsReader(cmd, sizeof(cmd));
+ CodeIso15693AsTag(cmd, sizeof(cmd));
}
// Universal Method for sending to and recv bytes from a tag
// init ... should we initialize the reader?
-// speed ... 0 low speed, 1 hi speed
+// speed ... 0 low speed, 1 hi speed
// **recv will return you a pointer to the received data
-// If you do not need the answer use NULL for *recv[]
+// If you do not need the answer use NULL for *recv[]
// return: lenght of received data
-int SendDataTag(uint8_t *send, int sendlen, int init, int speed, uint8_t **recv) {
+int SendDataTag(uint8_t *send, int sendlen, bool init, int speed, uint8_t **recv) {
- int samples = 0;
- int tsamples = 0;
- int wait = 0;
- int elapsed = 0;
-
LED_A_ON();
- LED_B_ON();
+ LED_B_OFF();
LED_C_OFF();
- LED_D_OFF();
-
+
if (init) Iso15693InitReader();
int answerLen=0;
// high speed (1 out of 4)
CodeIso15693AsReader(send, sendlen);
}
-
- LED_A_ON();
- LED_B_OFF();
-
- TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait);
+
+ TransmitTo15693Tag(ToSend,ToSendMax);
// Now wait for a response
if (recv!=NULL) {
- LED_A_OFF();
- LED_B_ON();
- answerLen = GetIso15693AnswerFromTag(answer, 100, &samples, &elapsed) ;
+ answerLen = GetIso15693AnswerFromTag(answer, 100);
*recv=answer;
}
LED_A_OFF();
- LED_B_OFF();
- LED_C_OFF();
- LED_D_OFF();
-
+
return answerLen;
}
// --------------------------------------------------------------------
-// Debug Functions
+// Debug Functions
// --------------------------------------------------------------------
// Decodes a message from a tag and displays its metadata and content
uint16_t crc;
if (len>3) {
- if (d[0]&(1<<3))
+ if (d[0]&(1<<3))
strncat(status,"ProtExt ",DBD15STATLEN);
- if (d[0]&1) {
+ if (d[0]&1) {
// error
strncat(status,"Error ",DBD15STATLEN);
switch (d[1]) {
- case 0x01:
+ case 0x01:
strncat(status,"01:notSupp",DBD15STATLEN);
break;
- case 0x02:
+ case 0x02:
strncat(status,"02:notRecog",DBD15STATLEN);
break;
- case 0x03:
+ case 0x03:
strncat(status,"03:optNotSupp",DBD15STATLEN);
break;
- case 0x0f:
+ case 0x0f:
strncat(status,"0f:noInfo",DBD15STATLEN);
break;
- case 0x10:
+ case 0x10:
strncat(status,"10:dontExist",DBD15STATLEN);
break;
- case 0x11:
+ case 0x11:
strncat(status,"11:lockAgain",DBD15STATLEN);
break;
- case 0x12:
+ case 0x12:
strncat(status,"12:locked",DBD15STATLEN);
break;
- case 0x13:
+ case 0x13:
strncat(status,"13:progErr",DBD15STATLEN);
break;
- case 0x14:
+ case 0x14:
strncat(status,"14:lockErr",DBD15STATLEN);
break;
default:
} else {
strncat(status,"NoErr ",DBD15STATLEN);
}
-
+
crc=Crc(d,len-2);
- if ( (( crc & 0xff ) == d[len-2]) && (( crc >> 8 ) == d[len-1]) )
+ if ( (( crc & 0xff ) == d[len-2]) && (( crc >> 8 ) == d[len-1]) )
strncat(status,"CrcOK",DBD15STATLEN);
else
- strncat(status,"CrcFail!",DBD15STATLEN);
+ strncat(status,"CrcFail!",DBD15STATLEN);
Dbprintf("%s",status);
}
return;
}
-
-
//-----------------------------------------------------------------------------
// Simulate an ISO15693 reader, perform anti-collision and then attempt to read a sector
// all demodulation performed in arm rather than host. - greg
//-----------------------------------------------------------------------------
void ReaderIso15693(uint32_t parameter)
{
+ LEDsoff();
LED_A_ON();
- LED_B_ON();
- LED_C_OFF();
- LED_D_OFF();
int answerLen1 = 0;
- int answerLen2 = 0;
- // int answerLen3 = 0;
- int i = 0;
- int samples = 0;
- int tsamples = 0;
- int wait = 0;
- int elapsed = 0;
uint8_t TagUID[8] = {0x00};
FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
uint8_t *answer1 = BigBuf_get_addr() + 4000;
- uint8_t *answer2 = BigBuf_get_addr() + 4100;
- // uint8_t *answer3 = BigBuf_get_addr() + 4200;
- // Blank arrays
memset(answer1, 0x00, 200);
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
// Setup SSC
- FpgaSetupSsc();
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
// Start from off (no field generated)
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
SpinDelay(200);
// Give the tags time to energize
+ LED_D_ON();
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
SpinDelay(200);
- LED_A_ON();
- LED_B_OFF();
- LED_C_OFF();
- LED_D_OFF();
-
// FIRST WE RUN AN INVENTORY TO GET THE TAG UID
// THIS MEANS WE CAN PRE-BUILD REQUESTS TO SAVE CPU TIME
// Now send the IDENTIFY command
BuildIdentifyRequest();
-
- TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait);
-
+
+ TransmitTo15693Tag(ToSend,ToSendMax);
+
// Now wait for a response
- answerLen1 = GetIso15693AnswerFromTag(answer1, 100, &samples, &elapsed) ;
+ answerLen1 = GetIso15693AnswerFromTag(answer1, 100) ;
if (answerLen1 >=12) // we should do a better check than this
{
}
Dbprintf("%d octets read from IDENTIFY request:", answerLen1);
- DbdecodeIso15693Answer(answerLen1,answer1);
- Dbhexdump(answerLen1,answer1,true);
+ DbdecodeIso15693Answer(answerLen1, answer1);
+ Dbhexdump(answerLen1, answer1, false);
// UID is reverse
- if (answerLen1>=12)
+ if (answerLen1 >= 12)
Dbprintf("UID = %02hX%02hX%02hX%02hX%02hX%02hX%02hX%02hX",
TagUID[7],TagUID[6],TagUID[5],TagUID[4],
TagUID[3],TagUID[2],TagUID[1],TagUID[0]);
// Dbhexdump(answerLen3,answer3,true);
// read all pages
- if (answerLen1>=12 && DEBUG) {
- i=0;
- while (i<32) { // sanity check, assume max 32 pages
- BuildReadBlockRequest(TagUID,i);
- TransmitTo15693Tag(ToSend,ToSendMax,&tsamples, &wait);
- answerLen2 = GetIso15693AnswerFromTag(answer2, 100, &samples, &elapsed);
- if (answerLen2>0) {
- Dbprintf("READ SINGLE BLOCK %d returned %d octets:",i,answerLen2);
- DbdecodeIso15693Answer(answerLen2,answer2);
- Dbhexdump(answerLen2,answer2,true);
- if ( *((uint32_t*) answer2) == 0x07160101 ) break; // exit on NoPageErr
- }
+ if (answerLen1 >= 12 && DEBUG) {
+ uint8_t *answer2 = BigBuf_get_addr() + 4100;
+ int i = 0;
+ while (i < 32) { // sanity check, assume max 32 pages
+ BuildReadBlockRequest(TagUID, i);
+ TransmitTo15693Tag(ToSend, ToSendMax);
+ int answerLen2 = GetIso15693AnswerFromTag(answer2, 100);
+ if (answerLen2 > 0) {
+ Dbprintf("READ SINGLE BLOCK %d returned %d octets:", i, answerLen2);
+ DbdecodeIso15693Answer(answerLen2, answer2);
+ Dbhexdump(answerLen2, answer2, false);
+ if ( *((uint32_t*) answer2) == 0x07160101 ) break; // exit on NoPageErr
+ }
i++;
- }
+ }
}
- LED_A_OFF();
- LED_B_OFF();
- LED_C_OFF();
+ // for the time being, switch field off to protect rdv4.0
+ // note: this prevents using hf 15 cmd with s option - which isn't implemented yet anyway
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
LED_D_OFF();
+
+ LED_A_OFF();
}
-// Simulate an ISO15693 TAG, perform anti-collision and then print any reader commands
-// all demodulation performed in arm rather than host. - greg
+
+// Simulate an ISO15693 TAG.
+// For Inventory command: print command and send Inventory Response with given UID
+// TODO: interpret other reader commands and send appropriate response
void SimTagIso15693(uint32_t parameter, uint8_t *uid)
{
+ LEDsoff();
LED_A_ON();
- LED_B_ON();
- LED_C_OFF();
- LED_D_OFF();
-
- int answerLen1 = 0;
- int samples = 0;
- int tsamples = 0;
- int wait = 0;
- int elapsed = 0;
FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-
- uint8_t *buf = BigBuf_get_addr() + 4000;
- memset(buf, 0x00, 100);
-
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- FpgaSetupSsc();
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_NO_MODULATION);
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_SIMULATOR);
- // Start from off (no field generated)
- FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
- SpinDelay(200);
+ StartCountSspClk();
- LED_A_OFF();
- LED_B_OFF();
- LED_C_ON();
- LED_D_OFF();
+ uint8_t cmd[ISO15693_MAX_COMMAND_LENGTH];
+
+ // Build a suitable response to the reader INVENTORY command
+ BuildInventoryResponse(uid);
// Listen to reader
- answerLen1 = GetIso15693AnswerFromSniff(buf, 100, &samples, &elapsed) ;
+ while (!BUTTON_PRESS()) {
+ uint32_t eof_time = 0, start_time = 0;
+ int cmd_len = GetIso15693CommandFromReader(cmd, sizeof(cmd), &eof_time);
+
+ if ((cmd_len >= 5) && (cmd[0] & ISO15693_REQ_INVENTORY) && (cmd[1] == ISO15693_INVENTORY)) { // TODO: check more flags
+ bool slow = !(cmd[0] & ISO15693_REQ_DATARATE_HIGH);
+ start_time = eof_time + DELAY_ISO15693_VCD_TO_VICC - DELAY_ARM_TO_READER;
+ TransmitTo15693Reader(ToSend, ToSendMax, start_time, slow);
+ }
- if (answerLen1 >=1) // we should do a better check than this
- {
- // Build a suitable reponse to the reader INVENTORY cocmmand
- // not so obsvious, but in the call to BuildInventoryResponse, the command is copied to the global ToSend buffer used below.
-
- BuildInventoryResponse(uid);
-
- TransmitTo15693Reader(ToSend,ToSendMax, &tsamples, &wait);
+ Dbprintf("%d bytes read from reader:", cmd_len);
+ Dbhexdump(cmd_len, cmd, false);
}
- Dbprintf("%d octets read from reader command: %x %x %x %x %x %x %x %x %x", answerLen1,
- buf[0], buf[1], buf[2], buf[3],
- buf[4], buf[5], buf[6], buf[7], buf[8]);
-
- Dbprintf("Simulationg uid: %x %x %x %x %x %x %x %x",
- uid[0], uid[1], uid[2], uid[3],
- uid[4], uid[5], uid[6], uid[7]);
-
- LED_A_OFF();
- LED_B_OFF();
- LED_C_OFF();
- LED_D_OFF();
+ LEDsoff();
}
// Since there is no standardized way of reading the AFI out of a tag, we will brute force it
// (some manufactures offer a way to read the AFI, though)
-void BruteforceIso15693Afi(uint32_t speed)
-{
+void BruteforceIso15693Afi(uint32_t speed)
+{
+ LEDsoff();
+ LED_A_ON();
+
uint8_t data[20];
uint8_t *recv=data;
int datalen=0, recvlen=0;
-
+
Iso15693InitReader();
-
+
// first without AFI
- // Tags should respond wihtout AFI and with AFI=0 even when AFI is active
-
- data[0]=ISO15_REQ_SUBCARRIER_SINGLE | ISO15_REQ_DATARATE_HIGH |
- ISO15_REQ_INVENTORY | ISO15_REQINV_SLOT1;
- data[1]=ISO15_CMD_INVENTORY;
- data[2]=0; // mask length
- datalen=AddCrc(data,3);
- recvlen=SendDataTag(data,datalen,0,speed,&recv);
+ // Tags should respond without AFI and with AFI=0 even when AFI is active
+
+ data[0] = ISO15693_REQ_DATARATE_HIGH | ISO15693_REQ_INVENTORY | ISO15693_REQINV_SLOT1;
+ data[1] = ISO15693_INVENTORY;
+ data[2] = 0; // mask length
+ datalen = AddCrc(data,3);
+ recvlen = SendDataTag(data, datalen, false, speed, &recv);
WDT_HIT();
if (recvlen>=12) {
Dbprintf("NoAFI UID=%s",sprintUID(NULL,&recv[2]));
}
-
+
// now with AFI
-
- data[0]=ISO15_REQ_SUBCARRIER_SINGLE | ISO15_REQ_DATARATE_HIGH |
- ISO15_REQ_INVENTORY | ISO15_REQINV_AFI | ISO15_REQINV_SLOT1;
- data[1]=ISO15_CMD_INVENTORY;
- data[2]=0; // AFI
- data[3]=0; // mask length
-
+
+ data[0] = ISO15693_REQ_DATARATE_HIGH | ISO15693_REQ_INVENTORY | ISO15693_REQINV_AFI | ISO15693_REQINV_SLOT1;
+ data[1] = ISO15693_INVENTORY;
+ data[2] = 0; // AFI
+ data[3] = 0; // mask length
+
for (int i=0;i<256;i++) {
data[2]=i & 0xFF;
datalen=AddCrc(data,4);
- recvlen=SendDataTag(data,datalen,0,speed,&recv);
+ recvlen=SendDataTag(data, datalen, false, speed, &recv);
WDT_HIT();
if (recvlen>=12) {
- Dbprintf("AFI=%i UID=%s",i,sprintUID(NULL,&recv[2]));
+ Dbprintf("AFI=%i UID=%s", i, sprintUID(NULL,&recv[2]));
}
- }
+ }
Dbprintf("AFI Bruteforcing done.");
-
+
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+ LEDsoff();
}
// Allows to directly send commands to the tag via the client
-void DirectTag15693Command(uint32_t datalen,uint32_t speed, uint32_t recv, uint8_t data[]) {
+void DirectTag15693Command(uint32_t datalen, uint32_t speed, uint32_t recv, uint8_t data[]) {
int recvlen=0;
uint8_t *recvbuf = BigBuf_get_addr();
-// UsbCommand n;
-
+
+ LED_A_ON();
+
if (DEBUG) {
Dbprintf("SEND");
- Dbhexdump(datalen,data,true);
+ Dbhexdump(datalen, data, false);
}
-
- recvlen=SendDataTag(data,datalen,1,speed,(recv?&recvbuf:NULL));
-
- if (recv) {
- LED_B_ON();
- cmd_send(CMD_ACK,recvlen>48?48:recvlen,0,0,recvbuf,48);
- LED_B_OFF();
-
+
+ recvlen = SendDataTag(data, datalen, true, speed, (recv?&recvbuf:NULL));
+
+ if (recv) {
+ cmd_send(CMD_ACK, recvlen>48?48:recvlen, 0, 0, recvbuf, 48);
+
if (DEBUG) {
Dbprintf("RECV");
- DbdecodeIso15693Answer(recvlen,recvbuf);
- Dbhexdump(recvlen,recvbuf,true);
+ DbdecodeIso15693Answer(recvlen,recvbuf);
+ Dbhexdump(recvlen, recvbuf, false);
}
}
+ // for the time being, switch field off to protect rdv4.0
+ // note: this prevents using hf 15 cmd with s option - which isn't implemented yet anyway
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+ LED_D_OFF();
+
+ LED_A_OFF();
}
projects / proxmark3-svn / blobdiff