//-----------------------------------------------------------------------------
// Jonathan Westhues, split Nov 2006
+// piwi 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
#include "iso14443crc.h"
-#define RECEIVE_SAMPLES_TIMEOUT 2000
-#define ISO14443B_DMA_BUFFER_SIZE 256
+#define RECEIVE_SAMPLES_TIMEOUT 1000 // TR0 max is 256/fs = 256/(848kHz) = 302us or 64 samples from FPGA. 1000 seems to be much too high?
+#define ISO14443B_DMA_BUFFER_SIZE 128
// PCB Block number for APDUs
static uint8_t pcb_blocknum = 0;
LED_A_OFF(); // Finished receiving
Uart.state = STATE_UNSYNCD;
if (Uart.byteCnt != 0) {
- return TRUE;
+ return true;
}
} else {
// this is an error
break;
}
- return FALSE;
+ return false;
}
// 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).
+// (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.
for(;;) {
WDT_HIT();
- if(BUTTON_PRESS()) return FALSE;
+ if(BUTTON_PRESS()) return false;
if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
for(uint8_t mask = 0x80; mask != 0x00; mask >>= 1) {
if(Handle14443bUartBit(b & mask)) {
*len = Uart.byteCnt;
- return TRUE;
+ return true;
}
}
}
}
- return FALSE;
+ return false;
}
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
void SimulateIso14443bTag(void)
{
- // the only commands we understand is REQB, AFI=0, Select All, N=0:
- static const uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 };
- // ... and REQB, AFI=0, Normal Request, N=0:
- static const uint8_t cmd2[] = { 0x05, 0x00, 0x00, 0x71, 0xFF };
+ // the only commands we understand is WUPB, AFI=0, Select All, N=1:
+ static const uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 }; // WUPB
+ // ... and REQB, AFI=0, Normal Request, N=1:
+ static const uint8_t cmd2[] = { 0x05, 0x00, 0x00, 0x71, 0xFF }; // REQB
+ // ... and HLTB
+ static const uint8_t cmd3[] = { 0x50, 0xff, 0xff, 0xff, 0xff }; // HLTB
+ // ... and ATTRIB
+ static const uint8_t cmd4[] = { 0x1D, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; // ATTRIB
// ... and we always respond with ATQB, PUPI = 820de174, Application Data = 0x20381922,
// supports only 106kBit/s in both directions, max frame size = 32Bytes,
0x50, 0x82, 0x0d, 0xe1, 0x74, 0x20, 0x38, 0x19, 0x22,
0x00, 0x21, 0x85, 0x5e, 0xd7
};
+ // response to HLTB and ATTRIB
+ static const uint8_t response2[] = {0x00, 0x78, 0xF0};
+
FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
clear_trace();
- set_tracing(TRUE);
+ set_tracing(true);
const uint8_t *resp;
uint8_t *respCode;
memcpy(resp1Code, ToSend, ToSendMax);
uint16_t resp1CodeLen = ToSendMax;
+ // prepare the (other) tag answer:
+ CodeIso14443bAsTag(response2, sizeof(response2));
+ uint8_t *resp2Code = BigBuf_malloc(ToSendMax);
+ memcpy(resp2Code, ToSend, ToSendMax);
+ uint16_t resp2CodeLen = ToSendMax;
+
// We need to listen to the high-frequency, peak-detected path.
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- FpgaSetupSsc();
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_SIMULATOR);
cmdsRecvd = 0;
if (tracing) {
uint8_t parity[MAX_PARITY_SIZE];
- LogTrace(receivedCmd, len, 0, 0, parity, TRUE);
+ LogTrace(receivedCmd, len, 0, 0, parity, true);
}
// Good, look at the command now.
respLen = sizeof(response1);
respCode = resp1Code;
respCodeLen = resp1CodeLen;
+ } else if ( (len == sizeof(cmd3) && receivedCmd[0] == cmd3[0])
+ || (len == sizeof(cmd4) && receivedCmd[0] == cmd4[0]) ) {
+ resp = response2;
+ respLen = sizeof(response2);
+ respCode = resp2Code;
+ respCodeLen = resp2CodeLen;
} else {
Dbprintf("new cmd from reader: len=%d, cmdsRecvd=%d", len, cmdsRecvd);
// And print whether the CRC fails, just for good measure
uint8_t b1, b2;
- 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");
+ 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");
+ }
}
- break;
+ //get rid of compiler warning
+ respCodeLen = 0;
+ resp = response1;
+ respLen = 0;
+ respCode = resp1Code;
+ //don't crash at new command just wait and see if reader will send other new cmds.
+ //break;
}
cmdsRecvd++;
LED_D_OFF();
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SIMULATOR | FPGA_HF_SIMULATOR_MODULATE_BPSK);
AT91C_BASE_SSC->SSC_THR = 0xff;
- FpgaSetupSsc();
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_SIMULATOR);
// Transmit the response.
uint16_t i = 0;
// trace the response:
if (tracing) {
uint8_t parity[MAX_PARITY_SIZE];
- LogTrace(resp, respLen, 0, 0, parity, FALSE);
+ LogTrace(resp, respLen, 0, 0, parity, false);
}
}
#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; \
- if(v < 0) v = -v; \
- if(cq > 0) { \
- v += 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() { \
- if(ci < 0) { \
- if(cq < 0) { /* ci < 0, cq < 0 */ \
- if (cq < ci) { \
- v = -cq - (ci >> 1); \
- } else { \
- v = -ci - (cq >> 1); \
- } \
- } else { /* ci < 0, cq >= 0 */ \
- if (cq < -ci) { \
- v = -ci + (cq >> 1); \
- } else { \
- v = cq - (ci >> 1); \
- } \
- } \
- } else { \
- if(cq < 0) { /* ci >= 0, cq < 0 */ \
- if (-cq < ci) { \
- v = ci - (cq >> 1); \
- } else { \
- v = -cq + (ci >> 1); \
- } \
- } else { /* ci >= 0, cq >= 0 */ \
- if (cq < ci) { \
- v = ci + (cq >> 1); \
- } else { \
- v = cq + (ci >> 1); \
- } \
- } \
- } \
- }
-
+#define AMPLITUDE(ci,cq) (MAX(ABS(ci),ABS(cq)) + (MIN(ABS(ci),ABS(cq))/2))
switch(Demod.state) {
case DEMOD_UNSYNCD:
- CHECK_FOR_SUBCARRIER();
- if(v > SUBCARRIER_DETECT_THRESHOLD) { // subcarrier detected
+ if(AMPLITUDE(ci,cq) > SUBCARRIER_DETECT_THRESHOLD) { // subcarrier detected
Demod.state = DEMOD_PHASE_REF_TRAINING;
Demod.sumI = ci;
Demod.sumQ = cq;
case DEMOD_PHASE_REF_TRAINING:
if(Demod.posCount < 8) {
- CHECK_FOR_SUBCARRIER();
- if (v > SUBCARRIER_DETECT_THRESHOLD) {
+ if (AMPLITUDE(ci,cq) > 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;
LED_C_OFF();
if(s == 0x000) {
// This is EOF (start, stop and all data bits == '0'
- return TRUE;
+ return true;
}
}
}
break;
}
- return FALSE;
+ return false;
}
/*
* Demodulate the samples we received from the tag, also log to tracebuffer
- * quiet: set to 'TRUE' to disable debug output
+ * quiet: set to 'true' to disable debug output
*/
static void GetSamplesFor14443bDemod(int n, bool quiet)
{
- int max = 0;
- bool gotFrame = FALSE;
- int lastRxCounter, ci, cq, samples = 0;
-
+ int maxBehindBy = 0;
+ bool gotFrame = false;
+ int lastRxCounter, samples = 0;
+ int8_t ci, cq;
+
// Allocate memory from BigBuf for some buffers
// free all previous allocations first
BigBuf_free();
uint8_t *receivedResponse = 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);
+ uint16_t *dmaBuf = (uint16_t*) BigBuf_malloc(ISO14443B_DMA_BUFFER_SIZE * sizeof(uint16_t));
// Set up the demodulator for tag -> reader responses.
DemodInit(receivedResponse);
+ // wait for last transfer to complete
+ while (!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXEMPTY))
+
// Setup and start DMA.
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE);
- int8_t *upTo = dmaBuf;
+ uint16_t *upTo = dmaBuf;
lastRxCounter = ISO14443B_DMA_BUFFER_SIZE;
// Signal field is ON with the appropriate LED:
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
for(;;) {
- int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR;
- if(behindBy > max) max = behindBy;
-
- while(((lastRxCounter-AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO14443B_DMA_BUFFER_SIZE-1)) > 2) {
- ci = upTo[0];
- cq = upTo[1];
- upTo += 2;
- if(upTo >= dmaBuf + ISO14443B_DMA_BUFFER_SIZE) {
- upTo = dmaBuf;
- AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
- AT91C_BASE_PDC_SSC->PDC_RNCR = ISO14443B_DMA_BUFFER_SIZE;
- }
- lastRxCounter -= 2;
- if(lastRxCounter <= 0) {
- lastRxCounter += ISO14443B_DMA_BUFFER_SIZE;
- }
+ int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO14443B_DMA_BUFFER_SIZE-1);
+ if(behindBy > maxBehindBy) {
+ maxBehindBy = behindBy;
+ }
- samples += 2;
+ if(behindBy < 1) continue;
- if(Handle14443bSamplesDemod(ci, cq)) {
- gotFrame = TRUE;
- break;
- }
+ ci = *upTo >> 8;
+ cq = *upTo;
+ upTo++;
+ lastRxCounter--;
+ if(upTo >= dmaBuf + ISO14443B_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content.
+ upTo = dmaBuf; // start reading the circular buffer from the beginning
+ lastRxCounter += ISO14443B_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 = ISO14443B_DMA_BUFFER_SIZE; // DMA Next Counter registers
+ }
+ samples++;
+
+ if(Handle14443bSamplesDemod(ci, cq)) {
+ gotFrame = true;
+ break;
}
- if(samples > n || gotFrame) {
+ if(samples > n) {
break;
}
}
- AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
+ FpgaDisableSscDma();
- if (!quiet) Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Demod.len = %d, Demod.sumI = %d, Demod.sumQ = %d", max, samples, gotFrame, Demod.len, Demod.sumI, Demod.sumQ);
+ if (!quiet) Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Demod.len = %d, Demod.sumI = %d, Demod.sumQ = %d", maxBehindBy, samples, gotFrame, Demod.len, Demod.sumI, Demod.sumQ);
//Tracing
if (tracing && Demod.len > 0) {
uint8_t parity[MAX_PARITY_SIZE];
- LogTrace(Demod.output, Demod.len, 0, 0, parity, FALSE);
+ LogTrace(Demod.output, Demod.len, 0, 0, parity, false);
}
}
{
int c;
- FpgaSetupSsc();
-
- while(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
- AT91C_BASE_SSC->SSC_THR = 0xff;
- }
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_TX);
// Signal field is ON with the appropriate Red LED
LED_D_ON();
LED_B_ON();
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
- for(c = 0; c < 10;) {
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
- AT91C_BASE_SSC->SSC_THR = 0xff;
- 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 = ToSend[c];
+ AT91C_BASE_SSC->SSC_THR = ~ToSend[c];
c++;
if(c >= ToSendMax) {
break;
}
}
- if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
- volatile uint32_t r = AT91C_BASE_SSC->SSC_RHR;
- (void)r;
- }
WDT_HIT();
}
LED_B_OFF(); // Finished sending
ToSendReset();
- // Establish initial reference level
- for(i = 0; i < 40; i++) {
- ToSendStuffBit(1);
- }
// Send SOF
for(i = 0; i < 10; i++) {
ToSendStuffBit(0);
}
+ ToSendStuffBit(1);
+ ToSendStuffBit(1);
for(i = 0; i < len; i++) {
- // Stop bits/EGT
- ToSendStuffBit(1);
- ToSendStuffBit(1);
// Start bit
ToSendStuffBit(0);
// Data bits
}
b >>= 1;
}
+ // Stop bit
+ ToSendStuffBit(1);
}
+
// Send EOF
- ToSendStuffBit(1);
for(i = 0; i < 10; i++) {
ToSendStuffBit(0);
}
- for(i = 0; i < 8; i++) {
- ToSendStuffBit(1);
- }
+ 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 < 24; i++) {
+ // ensure that last byte is filled up
+ for(i = 0; i < 8; i++) {
ToSendStuffBit(1);
}
TransmitFor14443b();
if (tracing) {
uint8_t parity[MAX_PARITY_SIZE];
- LogTrace(cmd,len, 0, 0, parity, TRUE);
+ LogTrace(cmd,len, 0, 0, parity, true);
}
}
// 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;
// first, wake up the tag
CodeAndTransmit14443bAsReader(wupb, sizeof(wupb));
- GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
+ GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true);
// ATQB too short?
if (Demod.len < 14)
{
attrib[7] = Demod.output[10] & 0x0F;
ComputeCrc14443(CRC_14443_B, attrib, 9, attrib + 9, attrib + 10);
CodeAndTransmit14443bAsReader(attrib, sizeof(attrib));
- GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
+ GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true);
// Answer to ATTRIB too short?
if(Demod.len < 3)
{
void iso14443b_setup() {
FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
// Set up the synchronous serial port
- FpgaSetupSsc();
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_TX);
// connect Demodulated Signal to ADC:
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
LED_D_ON();
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
- // Start the timer
- StartCountSspClk();
-
DemodReset();
UartReset();
}
SpinDelay(200);
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- FpgaSetupSsc();
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
// Now give it time to spin up.
// Signal field is on with the appropriate LED
SpinDelay(200);
clear_trace();
- set_tracing(TRUE);
+ set_tracing(true);
// First command: wake up the tag using the INITIATE command
uint8_t cmd1[] = {0x06, 0x00, 0x97, 0x5b};
CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
- GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
+ GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true);
if (Demod.len == 0) {
DbpString("No response from tag");
+ LED_D_OFF();
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
return;
} else {
Dbprintf("Randomly generated Chip ID (+ 2 byte CRC): %02x %02x %02x",
cmd1[1] = Demod.output[0];
ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);
CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
- GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
+ GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true);
if (Demod.len != 3) {
Dbprintf("Expected 3 bytes from tag, got %d", Demod.len);
+ LED_D_OFF();
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
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.");
+ LED_D_OFF();
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
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]);
+ LED_D_OFF();
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
return;
}
cmd1[0] = 0x0B;
ComputeCrc14443(CRC_14443_B, cmd1, 1 , &cmd1[1], &cmd1[2]);
CodeAndTransmit14443bAsReader(cmd1, 3); // Only first three bytes for this one
- GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
+ GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true);
if (Demod.len != 10) {
Dbprintf("Expected 10 bytes from tag, got %d", Demod.len);
+ LED_D_OFF();
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
return;
}
// The check the CRC of the answer (use cmd1 as temporary variable):
cmd1[1] = i;
ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);
CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
- GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
+ GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true);
if (Demod.len != 6) { // Check if we got an answer from the tag
DbpString("Expected 6 bytes from tag, got less...");
+ LED_D_OFF();
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
return;
}
// The check the CRC of the answer (use cmd1 as temporary variable):
}
i++;
}
+
+ LED_D_OFF();
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
}
*/
void RAMFUNC SnoopIso14443b(void)
{
- // 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 = TRUE; // TODO: set and evaluate trigger condition
-
FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
BigBuf_free();
clear_trace();
- set_tracing(TRUE);
+ set_tracing(true);
// The DMA buffer, used to stream samples from the FPGA
- int8_t *dmaBuf = (int8_t*) BigBuf_malloc(ISO14443B_DMA_BUFFER_SIZE);
+ uint16_t *dmaBuf = (uint16_t*) BigBuf_malloc(ISO14443B_DMA_BUFFER_SIZE * sizeof(uint16_t));
int lastRxCounter;
- int8_t *upTo;
- int ci, cq;
+ uint16_t *upTo;
+ int8_t ci, cq;
int maxBehindBy = 0;
// Count of samples received so far, so that we can include timing
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
// Setup for the DMA.
- FpgaSetupSsc();
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_RX_XCORR);
upTo = dmaBuf;
lastRxCounter = ISO14443B_DMA_BUFFER_SIZE;
FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE);
uint8_t parity[MAX_PARITY_SIZE];
- bool TagIsActive = FALSE;
- bool ReaderIsActive = FALSE;
+ bool TagIsActive = false;
+ bool ReaderIsActive = false;
+ // 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
+ // reader command
+ bool triggered = false;
// And now we loop, receiving samples.
for(;;) {
- int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) &
- (ISO14443B_DMA_BUFFER_SIZE-1);
+ int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO14443B_DMA_BUFFER_SIZE-1);
if(behindBy > maxBehindBy) {
maxBehindBy = behindBy;
}
- if(behindBy < 2) continue;
+ if(behindBy < 1) continue;
- ci = upTo[0];
- cq = upTo[1];
- upTo += 2;
- lastRxCounter -= 2;
- if(upTo >= dmaBuf + ISO14443B_DMA_BUFFER_SIZE) {
- upTo = dmaBuf;
+ ci = *upTo>>8;
+ cq = *upTo;
+ upTo++;
+ lastRxCounter--;
+ if(upTo >= dmaBuf + ISO14443B_DMA_BUFFER_SIZE) { // we have read all of the DMA buffer content.
+ upTo = dmaBuf; // start reading the circular buffer from the beginning again
lastRxCounter += ISO14443B_DMA_BUFFER_SIZE;
- AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf;
- AT91C_BASE_PDC_SSC->PDC_RNCR = ISO14443B_DMA_BUFFER_SIZE;
- WDT_HIT();
- if(behindBy > (9*ISO14443B_DMA_BUFFER_SIZE/10)) { // TODO: understand whether we can increase/decrease as we want or not?
- Dbprintf("blew circular buffer! behindBy=%d", behindBy);
- break;
- }
- if(!tracing) {
- DbpString("Reached trace limit");
+ if(behindBy > (9*ISO14443B_DMA_BUFFER_SIZE/10)) {
+ Dbprintf("About to blow circular buffer - aborted! behindBy=%d", behindBy);
break;
}
+ }
+ 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 = ISO14443B_DMA_BUFFER_SIZE; // DMA Next Counter registers
+ WDT_HIT();
if(BUTTON_PRESS()) {
DbpString("cancelled");
break;
}
}
- samples += 2;
+ samples++;
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);
+ triggered = true;
+ if(tracing) {
+ LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, true);
}
/* And ready to receive another command. */
UartReset();
DemodReset();
}
if(Handle14443bUartBit(cq & 0x01)) {
- if(triggered && tracing) {
- LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE);
+ triggered = true;
+ if(tracing) {
+ LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, true);
}
/* And ready to receive another command. */
UartReset();
ReaderIsActive = (Uart.state > STATE_GOT_FALLING_EDGE_OF_SOF);
}
- if(!ReaderIsActive) { // no need to try decoding tag data if the reader is sending - and we cannot afford the time
- if(Handle14443bSamplesDemod(ci | 0x01, cq | 0x01)) {
+ if(!ReaderIsActive && triggered) { // no need to try decoding tag data if the reader is sending or not yet triggered
+ if(Handle14443bSamplesDemod(ci/2, cq/2)) {
//Use samples as a time measurement
if(tracing)
{
uint8_t parity[MAX_PARITY_SIZE];
- LogTrace(Demod.output, Demod.len, samples, samples, parity, FALSE);
+ LogTrace(Demod.output, Demod.len, samples, samples, parity, false);
}
- triggered = TRUE;
-
// And ready to receive another response.
DemodReset();
}
FpgaDisableSscDma();
LEDsoff();
- AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
DbpString("Snoop statistics:");
Dbprintf(" Max behind by: %i", maxBehindBy);
Dbprintf(" Uart State: %x", Uart.state);
{
FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
- FpgaSetupSsc();
-
- set_tracing(TRUE);
-
- CodeAndTransmit14443bAsReader(data, datalen);
- if(recv) {
- GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
- uint16_t iLen = MIN(Demod.len, USB_CMD_DATA_SIZE);
- cmd_send(CMD_ACK, iLen, 0, 0, Demod.output, iLen);
+ // switch field on and give tag some time to power up
+ LED_D_ON();
+ FpgaSetupSsc(FPGA_MAJOR_MODE_HF_READER_TX);
+ SpinDelay(10);
+
+ if (datalen){
+ set_tracing(true);
+
+ CodeAndTransmit14443bAsReader(data, datalen);
+
+ if(recv) {
+ GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true);
+ uint16_t iLen = MIN(Demod.len, USB_CMD_DATA_SIZE);
+ cmd_send(CMD_ACK, iLen, 0, 0, Demod.output, iLen);
+ }
}
if(!powerfield) {
projects / proxmark3-svn / blobdiff