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iso15 sniff: improve iso15 FSK decoding (ARM part)

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Yann GASCUEL 2022-03-04 12:32:08 +01:00
commit 3e784557fc
1 changed files with 187 additions and 144 deletions
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331
armsrc/iso15693.c
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@ -1280,21 +1280,22 @@ void AcquireRawAdcSamplesIso15693(void) {
typedef struct DecodeTagFSK { typedef struct DecodeTagFSK {
enum { enum {
STATE_FSK_ERROR,
STATE_FSK_BEFORE_SOF, STATE_FSK_BEFORE_SOF,
STATE_FSK_SOF_484, STATE_FSK_SOF_484,
STATE_FSK_SOF_424, STATE_FSK_SOF_424,
STATE_FSK_SOF_END, STATE_FSK_SOF_END_484,
STATE_FSK_SOF_END_424,
STATE_FSK_RECEIVING_DATA_484, STATE_FSK_RECEIVING_DATA_484,
STATE_FSK_RECEIVING_DATA_424, STATE_FSK_RECEIVING_DATA_424,
STATE_FSK_EOF, STATE_FSK_EOF
STATE_FSK_ERROR
} state; } state;
enum { enum {
LOGIC0_PART1, LOGIC0_PART1,
LOGIC1_PART1, LOGIC1_PART1,
LOGIC0_PART2, LOGIC0_PART2,
LOGIC1_PART2, LOGIC1_PART2,
SOF SOF
} lastBit; } lastBit;
uint8_t count; uint8_t count;
uint8_t bitCount; uint8_t bitCount;
@ -1309,7 +1310,6 @@ static void DecodeTagFSKReset(DecodeTagFSK_t *DecodeTag) {
DecodeTag->bitCount = 0; DecodeTag->bitCount = 0;
DecodeTag->len = 0; DecodeTag->len = 0;
DecodeTag->shiftReg = 0; DecodeTag->shiftReg = 0;
DbpString("FSK tag reset");
} }
static void DecodeTagFSKInit(DecodeTagFSK_t *DecodeTag, uint8_t *data, uint16_t max_len) { static void DecodeTagFSKInit(DecodeTagFSK_t *DecodeTag, uint8_t *data, uint16_t max_len) {
@ -1320,7 +1320,7 @@ static void DecodeTagFSKInit(DecodeTagFSK_t *DecodeTag, uint8_t *data, uint16_t
// Performances of this function are crutial for stability // Performances of this function are crutial for stability
// as it is called in real time for every samples // as it is called in real time for every samples
static int RAMFUNC Handle15693FSKSamplesFromTag(uint8_t freq, DecodeTagFSK_t *DecodeTag, bool recv_speed, int samples) static int RAMFUNC Handle15693FSKSamplesFromTag(uint8_t freq, DecodeTagFSK_t *DecodeTag, bool recv_speed)
{ {
switch(DecodeTag->state) { switch(DecodeTag->state) {
case STATE_FSK_BEFORE_SOF: case STATE_FSK_BEFORE_SOF:
@ -1334,16 +1334,15 @@ static int RAMFUNC Handle15693FSKSamplesFromTag(uint8_t freq, DecodeTagFSK_t *De
case STATE_FSK_SOF_484: case STATE_FSK_SOF_484:
//DbpString("STATE_FSK_SOF_484"); //DbpString("STATE_FSK_SOF_484");
if (FREQ_IS_424(freq) && SEOF_COUNT(DecodeTag->count, recv_speed))
if (FREQ_IS_484(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still in SOF at 484
{
DecodeTag->count++;
}
else if (FREQ_IS_424(freq) && SEOF_COUNT(DecodeTag->count, recv_speed))
{ // SOF part1 continue at 424 { // SOF part1 continue at 424
DecodeTag->state = STATE_FSK_SOF_424; DecodeTag->state = STATE_FSK_SOF_424;
DecodeTag->count = 1; DecodeTag->count = 1;
} }
else if (FREQ_IS_484(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still in SOF at 484
{
DecodeTag->count++;
}
else // SOF failed, roll back else // SOF failed, roll back
{ {
DecodeTag->state = STATE_FSK_BEFORE_SOF; DecodeTag->state = STATE_FSK_BEFORE_SOF;
@ -1352,103 +1351,136 @@ static int RAMFUNC Handle15693FSKSamplesFromTag(uint8_t freq, DecodeTagFSK_t *De
case STATE_FSK_SOF_424: case STATE_FSK_SOF_424:
//DbpString("STATE_FSK_SOF_424"); //DbpString("STATE_FSK_SOF_424");
if (FREQ_IS_484(freq) && SEOF_COUNT(DecodeTag->count, recv_speed))
if (FREQ_IS_424(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still in SOF at 424
DecodeTag->count++;
else if (FREQ_IS_484(freq) && SEOF_COUNT(DecodeTag->count, recv_speed))
{ // SOF part 1 finished { // SOF part 1 finished
DecodeTag->state = STATE_FSK_SOF_END; DecodeTag->state = STATE_FSK_SOF_END_484;
DecodeTag->count = 1; DecodeTag->count = 1;
} }
else if (FREQ_IS_424(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still in SOF at 424
DecodeTag->count++;
else // SOF failed, roll back else // SOF failed, roll back
{ {
#ifdef DEBUG
if (DEBUG) if (DEBUG)
Dbprintf("SOF_424 failed: freq=%d, count=%d, recv_speed=%d", freq, DecodeTag->count, recv_speed); Dbprintf("SOF_424 failed: freq=%d, count=%d, recv_speed=%d", freq, DecodeTag->count, recv_speed);
#endif
DecodeTag->state = STATE_FSK_BEFORE_SOF; DecodeTag->state = STATE_FSK_BEFORE_SOF;
} }
break; break;
case STATE_FSK_SOF_END: case STATE_FSK_SOF_END_484:
if (FREQ_IS_484(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still in SOF_END (484) if (FREQ_IS_424(freq) && LOGIC_COUNT(DecodeTag->count, recv_speed))
DecodeTag->count++; {
else if (FREQ_IS_424(freq) && LOGIC_COUNT(DecodeTag->count, recv_speed)) DecodeTag->state = STATE_FSK_SOF_END_424;
{ // SOF END finished or SOF END 1st part finished
DecodeTag->count = 0;
if (DecodeTag->lastBit == SOF)
{ // SOF finished at 424
if (DEBUG)
DbpString("Receiving data !");
DecodeTag->state = STATE_FSK_RECEIVING_DATA_424;
LED_C_ON();
}
DecodeTag->lastBit = SOF;
}
else if (FREQ_IS_424(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still in SOF_END (424)
DecodeTag->count++;
else if (DecodeTag->lastBit == SOF && FREQ_IS_484(freq) &&
LOGIC_COUNT(DecodeTag->count, recv_speed))
{ // SOF finished at 484
DecodeTag->state = STATE_FSK_RECEIVING_DATA_484;
DecodeTag->count = 1; DecodeTag->count = 1;
LED_C_ON();
} }
else // SOF failed, roll back else if (FREQ_IS_484(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still in SOF_END_484
DecodeTag->count++;
else // SOF failed, roll back
{ {
#ifdef DEBUG
if (DEBUG) if (DEBUG)
Dbprintf("SOF_END failed: freq=%d, count=%d, recv_speed=%d", freq, DecodeTag->count, recv_speed); Dbprintf("SOF_END_484 failed: freq=%d, count=%d, recv_speed=%d", freq, DecodeTag->count, recv_speed);
#endif
DecodeTag->state = STATE_FSK_BEFORE_SOF; DecodeTag->state = STATE_FSK_BEFORE_SOF;
} }
break; break;
case STATE_FSK_SOF_END_424:
if (FREQ_IS_484(freq) && LOGIC_COUNT(DecodeTag->count, recv_speed))
{ // SOF finished at 484
DecodeTag->count = 1;
DecodeTag->lastBit = SOF;
DecodeTag->state = STATE_FSK_RECEIVING_DATA_484;
LED_C_ON();
}
else if (FREQ_IS_424(freq) && LOGIC_COUNT(DecodeTag->count-2, recv_speed))
{ // SOF finished at 424 (wait count+2 to be sure that next freq is 424)
DecodeTag->count = 2;
DecodeTag->lastBit = SOF;
DecodeTag->state = STATE_FSK_RECEIVING_DATA_424;
LED_C_ON();
}
else if (FREQ_IS_424(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still in SOF_END_424
DecodeTag->count++;
else // SOF failed, roll back
{
#ifdef DEBUG
if (DEBUG)
Dbprintf("SOF_END_424 failed: freq=%d, count=%d, recv_speed=%d", freq, DecodeTag->count, recv_speed);
#endif
DecodeTag->state = STATE_FSK_BEFORE_SOF;
}
break;
case STATE_FSK_RECEIVING_DATA_424: case STATE_FSK_RECEIVING_DATA_424:
if (DecodeTag->lastBit == LOGIC1_PART1 && if (FREQ_IS_484(freq) && LOGIC_COUNT(DecodeTag->count, recv_speed))
LOGIC_COUNT(DecodeTag->count, recv_speed)) {
{ // logic 1 finished if (DecodeTag->lastBit == LOGIC1_PART1)
DecodeTag->lastBit = LOGIC1_PART2; { // logic 1 finished, goto 484
DecodeTag->count = 0; DecodeTag->lastBit = LOGIC1_PART2;
DecodeTag->shiftReg >>= 1; DecodeTag->shiftReg >>= 1;
DecodeTag->shiftReg |= 0x80; DecodeTag->shiftReg |= 0x80;
DecodeTag->bitCount++; DecodeTag->bitCount++;
if (DecodeTag->bitCount == 8) { if (DecodeTag->bitCount == 8) {
DecodeTag->output[DecodeTag->len++] = DecodeTag->shiftReg; DecodeTag->output[DecodeTag->len++] = DecodeTag->shiftReg;
if (DecodeTag->len > DecodeTag->max_len) { if (DecodeTag->len > DecodeTag->max_len) {
// buffer overflow, give up // buffer overflow, give up
LED_C_OFF(); LED_C_OFF();
return true; return true;
} }
DecodeTag->bitCount = 0; DecodeTag->bitCount = 0;
DecodeTag->shiftReg = 0; DecodeTag->shiftReg = 0;
} }
} }
else if (FREQ_IS_424(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still at 424 else
{ // end of LOGIC0_PART1
DecodeTag->lastBit = LOGIC0_PART1;
}
DecodeTag->count = 1;
DecodeTag->state = STATE_FSK_RECEIVING_DATA_484;
}
else if (FREQ_IS_424(freq) && LOGIC_COUNT(DecodeTag->count-2, recv_speed) &&
DecodeTag->lastBit == LOGIC1_PART1)
{ // logic 1 finished, stay in 484
DecodeTag->lastBit = LOGIC1_PART2;
DecodeTag->shiftReg >>= 1;
DecodeTag->shiftReg |= 0x80;
DecodeTag->bitCount++;
if (DecodeTag->bitCount == 8) {
DecodeTag->output[DecodeTag->len++] = DecodeTag->shiftReg;
if (DecodeTag->len > DecodeTag->max_len) {
// buffer overflow, give up
LED_C_OFF();
return true;
}
DecodeTag->bitCount = 0;
DecodeTag->shiftReg = 0;
}
DecodeTag->count = 2;
}
else if (FREQ_IS_424(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still at 424
DecodeTag->count++; DecodeTag->count++;
else if (FREQ_IS_484(freq) && LOGIC_COUNT(DecodeTag->count, recv_speed) &&
DecodeTag->lastBit >= LOGIC0_PART2)
{ // end of LOGIC0_PART1
DecodeTag->count = 1;
DecodeTag->state = STATE_FSK_RECEIVING_DATA_484;
DecodeTag->lastBit = LOGIC0_PART1;
}
else if (FREQ_IS_484(freq) && MIN_COUNT(DecodeTag->count, recv_speed))
{ // it was just the end of the previous block
DecodeTag->count = 1;
DecodeTag->state = STATE_FSK_RECEIVING_DATA_484;
}
else if (FREQ_IS_484(freq) && DecodeTag->lastBit == LOGIC0_PART2 && else if (FREQ_IS_484(freq) && DecodeTag->lastBit == LOGIC0_PART2 &&
SEOF_COUNT(DecodeTag->count, recv_speed)) SEOF_COUNT(DecodeTag->count, recv_speed))
{ // EOF has started { // EOF has started
#ifdef DEBUG
if (DEBUG) if (DEBUG)
Dbprintf("RECEIVING_DATA_424 failed: freq=%d, count=%d, recv_speed=%d", freq, DecodeTag->count, recv_speed); Dbprintf("RECEIVING_DATA_424->EOF: freq=%d, count=%d, recv_speed=%d, lastbit=%d, state=%d", freq, DecodeTag->count, recv_speed, DecodeTag->lastBit, DecodeTag->state);
#endif
DecodeTag->count = 1; DecodeTag->count = 1;
DecodeTag->state = STATE_FSK_EOF; DecodeTag->state = STATE_FSK_EOF;
LED_C_OFF(); LED_C_OFF();
} }
else // error else // error
{ {
#ifdef DEBUG
if (DEBUG) if (DEBUG)
Dbprintf("RECEIVING_DATA_424 error: freq=%d, count=%d, recv_speed=%d", freq, DecodeTag->count, recv_speed); Dbprintf("RECEIVING_DATA_424 error: freq=%d, count=%d, recv_speed=%d, lastbit=%d, state=%d", freq, DecodeTag->count, recv_speed, DecodeTag->lastBit, DecodeTag->state);
#endif
DecodeTag->state = STATE_FSK_ERROR; DecodeTag->state = STATE_FSK_ERROR;
LED_C_OFF(); LED_C_OFF();
return true; return true;
@ -1456,43 +1488,59 @@ static int RAMFUNC Handle15693FSKSamplesFromTag(uint8_t freq, DecodeTagFSK_t *De
break; break;
case STATE_FSK_RECEIVING_DATA_484: case STATE_FSK_RECEIVING_DATA_484:
if (DecodeTag->lastBit == LOGIC0_PART1 && if (FREQ_IS_424(freq) && LOGIC_COUNT(DecodeTag->count, recv_speed))
LOGIC_COUNT(DecodeTag->count, recv_speed)) {
{ // logic 0 finished if (DecodeTag->lastBit == LOGIC0_PART1)
DecodeTag->lastBit = LOGIC0_PART2; { // logic 0 finished, goto 424
DecodeTag->count = 0; DecodeTag->lastBit = LOGIC0_PART2;
DecodeTag->shiftReg >>= 1; DecodeTag->shiftReg >>= 1;
DecodeTag->bitCount++; DecodeTag->bitCount++;
if (DecodeTag->bitCount == 8) { if (DecodeTag->bitCount == 8) {
DecodeTag->output[DecodeTag->len++] = DecodeTag->shiftReg; DecodeTag->output[DecodeTag->len++] = DecodeTag->shiftReg;
if (DecodeTag->len > DecodeTag->max_len) { if (DecodeTag->len > DecodeTag->max_len) {
// buffer overflow, give up // buffer overflow, give up
LED_C_OFF(); LED_C_OFF();
return true; return true;
} }
DecodeTag->bitCount = 0; DecodeTag->bitCount = 0;
DecodeTag->shiftReg = 0; DecodeTag->shiftReg = 0;
} }
} }
else
{ // end of LOGIC1_PART1
DecodeTag->lastBit = LOGIC1_PART1;
}
DecodeTag->count = 1;
DecodeTag->state = STATE_FSK_RECEIVING_DATA_424;
}
else if (FREQ_IS_484(freq) && LOGIC_COUNT(DecodeTag->count-2, recv_speed) &&
DecodeTag->lastBit == LOGIC0_PART1)
{ // logic 0 finished, stay in 424
DecodeTag->lastBit = LOGIC0_PART2;
DecodeTag->shiftReg >>= 1;
DecodeTag->bitCount++;
if (DecodeTag->bitCount == 8) {
DecodeTag->output[DecodeTag->len++] = DecodeTag->shiftReg;
if (DecodeTag->len > DecodeTag->max_len) {
// buffer overflow, give up
LED_C_OFF();
return true;
}
DecodeTag->bitCount = 0;
DecodeTag->shiftReg = 0;
}
DecodeTag->count = 2;
}
else if (FREQ_IS_484(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still at 484 else if (FREQ_IS_484(freq) && !MAX_COUNT(DecodeTag->count, recv_speed)) // still at 484
DecodeTag->count++; DecodeTag->count++;
else if (FREQ_IS_424(freq) && LOGIC_COUNT(DecodeTag->count, recv_speed) && else // error
DecodeTag->lastBit >= LOGIC0_PART2)
{ // end of LOGIC1_PART1
DecodeTag->count = 1;
DecodeTag->state = STATE_FSK_RECEIVING_DATA_424;
DecodeTag->lastBit = LOGIC1_PART1;
}
else if (FREQ_IS_424(freq) && MIN_COUNT(DecodeTag->count, recv_speed))
{ // it was just the end of the previous block
DecodeTag->count = 1;
DecodeTag->state = STATE_FSK_RECEIVING_DATA_424;
}
else // error
{ {
#ifdef DEBUG
if (DEBUG) if (DEBUG)
Dbprintf("RECEIVING_DATA_484 error: freq=%d, count=%d, recv_speed=%d", freq, DecodeTag->count, recv_speed); Dbprintf("RECEIVING_DATA_484 error: freq=%d, count=%d, recv_speed=%d, lastbit=%d, state=%d", freq, DecodeTag->count, recv_speed, DecodeTag->lastBit, DecodeTag->state);
#endif
LED_C_OFF(); LED_C_OFF();
DecodeTag->state = STATE_FSK_ERROR; DecodeTag->state = STATE_FSK_ERROR;
return true; return true;
@ -1508,14 +1556,20 @@ static int RAMFUNC Handle15693FSKSamplesFromTag(uint8_t freq, DecodeTagFSK_t *De
} }
else // error else // error
{ {
#ifdef DEBUG
if (DEBUG) if (DEBUG)
Dbprintf("EOF error: freq=%d, count=%d, recv_speed=%d", freq, DecodeTag->count, recv_speed); Dbprintf("EOF error: freq=%d, count=%d, recv_speed=%d", freq, DecodeTag->count, recv_speed);
#endif
DecodeTag->state = STATE_FSK_ERROR; DecodeTag->state = STATE_FSK_ERROR;
return true; return true;
} }
break; break;
case STATE_FSK_ERROR: case STATE_FSK_ERROR:
LED_C_OFF(); LED_C_OFF();
#ifdef DEBUG
if (DEBUG)
Dbprintf("FSK error: freq=%d, count=%d, recv_speed=%d", freq, DecodeTag->count, recv_speed);
#endif
return true; // error return true; // error
break; break;
} }
@ -1587,7 +1641,9 @@ void SniffIso15693(uint8_t jam_search_len, uint8_t *jam_search_string) {
dma_start_time = GetCountSspClk() & 0xfffffff0; dma_start_time = GetCountSspClk() & 0xfffffff0;
} }
volatile uint16_t sniffdata = *upTo++; volatile uint16_t sniffdata;
volatile uint16_t sniffdata_prev = sniffdata;
sniffdata = *upTo++;
// we have read all of the DMA buffer content // we have read all of the DMA buffer content
if (upTo >= dma->buf + DMA_BUFFER_SIZE) { if (upTo >= dma->buf + DMA_BUFFER_SIZE) {
@ -1618,7 +1674,7 @@ void SniffIso15693(uint8_t jam_search_len, uint8_t *jam_search_string) {
} }
// no need to try decoding reader data if the tag is sending // no need to try decoding reader data if the tag is sending
if (tag_is_active == false) { if (!tag_is_active) {
if (Handle15693SampleFromReader((sniffdata & 0x02) >> 1, &dreader)) { if (Handle15693SampleFromReader((sniffdata & 0x02) >> 1, &dreader)) {
@ -1634,7 +1690,7 @@ void SniffIso15693(uint8_t jam_search_len, uint8_t *jam_search_string) {
expect_fast_answer = dreader.output[0] & ISO15_REQ_DATARATE_HIGH; expect_fast_answer = dreader.output[0] & ISO15_REQ_DATARATE_HIGH;
} }
// And ready to receive another command. // And ready to receive another command.
DecodeReaderReset(&dreader); //DecodeReaderReset(&dreader); // already reseted
DecodeTagReset(&dtag); DecodeTagReset(&dtag);
DecodeTagFSKReset(&dtagfsk); DecodeTagFSKReset(&dtagfsk);
reader_is_active = false; reader_is_active = false;
@ -1653,7 +1709,7 @@ void SniffIso15693(uint8_t jam_search_len, uint8_t *jam_search_string) {
expect_fast_answer = dreader.output[0] & ISO15_REQ_DATARATE_HIGH; expect_fast_answer = dreader.output[0] & ISO15_REQ_DATARATE_HIGH;
} }
// And ready to receive another command // And ready to receive another command
DecodeReaderReset(&dreader); //DecodeReaderReset(&dreader); // already reseted
DecodeTagReset(&dtag); DecodeTagReset(&dtag);
DecodeTagFSKReset(&dtagfsk); DecodeTagFSKReset(&dtagfsk);
reader_is_active = false; reader_is_active = false;
@ -1663,7 +1719,7 @@ void SniffIso15693(uint8_t jam_search_len, uint8_t *jam_search_string) {
} }
} }
if (reader_is_active == false && expect_tag_answer) { // no need to try decoding tag data if the reader is currently sending or no answer expected yet if (!reader_is_active && expect_tag_answer) { // no need to try decoding tag data if the reader is currently sending or no answer expected yet
if (!expect_fsk_answer) if (!expect_fsk_answer)
{ {
@ -1691,48 +1747,35 @@ void SniffIso15693(uint8_t jam_search_len, uint8_t *jam_search_string) {
} }
else else
{ {
if (Handle15693FSKSamplesFromTag((sniffdata >> 2) & 0x3, &dtagfsk, expect_fast_answer, samples-fsksamples)) { if (FREQ_IS_0((sniffdata >> 2) & 0x3)) // tolerate 1 00
uint32_t eof_time = dma_start_time + (samples * 16) - DELAY_TAG_TO_ARM_SNIFF; // end of EOF sniffdata = sniffdata_prev;
if (dtagfsk.lastBit == SOF) {
eof_time -= (8 * 16); // needed 8 additional samples to confirm single SOF (iCLASS)
}
uint32_t sof_time = eof_time
- dtagfsk.len * 8 * 8 * 16 // time for byte transfers
- (32 * 16) // time for SOF transfer
- (dtagfsk.lastBit != SOF ? (32 * 16) : 0); // time for EOF transfer
LogTrace_ISO15693(dtagfsk.output, dtagfsk.len, (sof_time * 4), (eof_time * 4), NULL, false); if (Handle15693FSKSamplesFromTag((sniffdata >> 2) & 0x3, &dtagfsk, expect_fast_answer)) {
// And ready to receive another response.
DecodeTagFSKReset(&dtagfsk);
DecodeTagReset(&dtag);
DecodeReaderReset(&dreader);
expect_tag_answer = false;
tag_is_active = false;
expect_fsk_answer = false; expect_fsk_answer = false;
} }
else if (Handle15693FSKSamplesFromTag(sniffdata & 0xFF, &dtagfsk, expect_fast_answer)) { else {
tag_is_active = (dtagfsk.state >= STATE_FSK_RECEIVING_DATA_484);
}
if (!expect_fsk_answer)
{ // FSK answer no more expected: switch back to ASK
if (dtagfsk.len > 0)
{
uint32_t eof_time = dma_start_time + (samples * 16) - DELAY_TAG_TO_ARM_SNIFF; // end of EOF
if (dtagfsk.lastBit == SOF) {
eof_time -= (8 * 16); // needed 8 additional samples to confirm single SOF (iCLASS)
}
uint32_t sof_time = eof_time
- dtagfsk.len * 8 * 8 * 16 // time for byte transfers
- (32 * 16) // time for SOF transfer
- (dtagfsk.lastBit != SOF ? (32 * 16) : 0); // time for EOF transfer
uint32_t eof_time = dma_start_time + (samples * 16) - DELAY_TAG_TO_ARM_SNIFF; // end of EOF LogTrace_ISO15693(dtagfsk.output, dtagfsk.len, (sof_time * 4), (eof_time * 4), NULL, false);
if (dtagfsk.lastBit == SOF) {
eof_time -= (8 * 16); // needed 8 additional samples to confirm single SOF (iCLASS)
} }
uint32_t sof_time = eof_time
- dtagfsk.len * 8 * 8 * 16 // time for byte transfers
- (32 * 16) // time for SOF transfer
- (dtagfsk.lastBit != SOF ? (32 * 16) : 0); // time for EOF transfer
LogTrace_ISO15693(dtagfsk.output, dtagfsk.len, (sof_time * 4), (eof_time * 4), NULL, false);
// And ready to receive another response.
DecodeTagFSKReset(&dtagfsk); DecodeTagFSKReset(&dtagfsk);
DecodeTagReset(&dtag);
DecodeReaderReset(&dreader); DecodeReaderReset(&dreader);
expect_tag_answer = false; expect_tag_answer = false;
tag_is_active = false; tag_is_active = false;
expect_fsk_answer = false;
} else {
tag_is_active = (dtagfsk.state >= STATE_FSK_RECEIVING_DATA_484);
} }
} }
} }