#include "crc16.h"
#include "string.h"
-// split into two routines so we can avoid timing issues after sending commands //
-void DoAcquisition125k_internal(bool silent)
+
+/**
+* Does the sample acquisition. If threshold is specified, the actual sampling
+* is not commenced until the threshold has been reached.
+* @param trigger_threshold - the threshold
+* @param silent - is true, now outputs are made. If false, dbprints the status
+*/
+void DoAcquisition125k_internal(int trigger_threshold,bool silent)
{
uint8_t *dest = (uint8_t *)BigBuf;
int n = sizeof(BigBuf);
}
if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
dest[i] = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
- i++;
LED_D_OFF();
- if (i >= n) break;
+ if (trigger_threshold != -1 && dest[i] < trigger_threshold)
+ continue;
+ else
+ trigger_threshold = -1;
+ if (++i >= n) break;
}
}
- if( ! silent)
+ if(!silent)
{
Dbprintf("buffer samples: %02x %02x %02x %02x %02x %02x %02x %02x ...",
dest[0], dest[1], dest[2], dest[3], dest[4], dest[5], dest[6], dest[7]);
+
}
}
-
-void DoAcquisition125k(void)
+/**
+* Perform sample aquisition.
+*/
+void DoAcquisition125k(int trigger_threshold)
{
- DoAcquisition125k_internal(false);
+ DoAcquisition125k_internal(trigger_threshold, false);
}
-void SetupToAcquireRawAdcSamples(int divisor)
+/**
+* Setup the FPGA to listen for samples. This method downloads the FPGA bitstream
+* if not already loaded, sets divisor and starts up the antenna.
+* @param divisor : 1, 88> 255 or negative ==> 134.8 KHz
+* 0 or 95 ==> 125 KHz
+*
+**/
+void LFSetupFPGAForADC(int divisor, bool lf_field)
{
+ FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
if ( (divisor == 1) || (divisor < 0) || (divisor > 255) )
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz
else if (divisor == 0)
else
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, divisor);
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | (lf_field ? FPGA_LF_ADC_READER_FIELD : 0));
// Connect the A/D to the peak-detected low-frequency path.
SetAdcMuxFor(GPIO_MUXSEL_LOPKD);
-
// Give it a bit of time for the resonant antenna to settle.
SpinDelay(50);
-
// Now set up the SSC to get the ADC samples that are now streaming at us.
FpgaSetupSsc();
}
-
+/**
+* Initializes the FPGA, and acquires the samples.
+**/
void AcquireRawAdcSamples125k(int divisor)
{
- SetupToAcquireRawAdcSamples(divisor);
+ LFSetupFPGAForADC(divisor, true);
// Now call the acquisition routine
- DoAcquisition125k_internal(false);
+ DoAcquisition125k_internal(-1,false);
+}
+/**
+* Initializes the FPGA for snoop-mode, and acquires the samples.
+**/
+
+void SnoopLFRawAdcSamples(int divisor, int trigger_threshold)
+{
+ LFSetupFPGAForADC(divisor, false);
+ DoAcquisition125k(trigger_threshold);
}
void ModThenAcquireRawAdcSamples125k(int delay_off, int period_0, int period_1, uint8_t *command)
{
- int at134khz;
/* Make sure the tag is reset */
+ FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
SpinDelay(2500);
+
+ int divisor_used = 95; // 125 KHz
// see if 'h' was specified
- if (command[strlen((char *) command) - 1] == 'h')
- at134khz = TRUE;
- else
- at134khz = FALSE;
- if (at134khz)
- FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz
- else
- FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
+ if (command[strlen((char *) command) - 1] == 'h')
+ divisor_used = 88; // 134.8 KHz
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaSendCommand(FPGA_CMD_SET_DIVISOR, divisor_used);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
// Give it a bit of time for the resonant antenna to settle.
SpinDelay(50);
+
// And a little more time for the tag to fully power up
SpinDelay(2000);
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
LED_D_OFF();
SpinDelayUs(delay_off);
- if (at134khz)
- FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz
- else
- FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
+ FpgaSendCommand(FPGA_CMD_SET_DIVISOR, divisor_used);
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
LED_D_ON();
if(*(command++) == '0')
SpinDelayUs(period_0);
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
LED_D_OFF();
SpinDelayUs(delay_off);
- if (at134khz)
- FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz
- else
- FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
+ FpgaSendCommand(FPGA_CMD_SET_DIVISOR, divisor_used);
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
// now do the read
- DoAcquisition125k();
+ DoAcquisition125k(-1);
}
/* blank r/w tag data stream
uint32_t threshold = (sampleslo - sampleshi + 1)>>1;
// TI tags charge at 134.2Khz
+ FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz
// Place FPGA in passthrough mode, in this mode the CROSS_LO line
// if not provided a valid crc will be computed from the data and written.
void WriteTItag(uint32_t idhi, uint32_t idlo, uint16_t crc)
{
+ FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
if(crc == 0) {
crc = update_crc16(crc, (idlo)&0xff);
crc = update_crc16(crc, (idlo>>8)&0xff);
int i;
uint8_t *tab = (uint8_t *)BigBuf;
+ FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_EDGE_DETECT);
AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DOUT | GPIO_SSC_CLK;
// threshold essentially we capture zero crossings for later analysis
uint8_t threshold_value = 127;
-
// sync to first lo-hi transition, and threshold
//Need to threshold first sample
size_t size=0,idx=0; //, found=0;
uint32_t hi2=0, hi=0, lo=0;
+ // Configure to go in 125Khz listen mode
+ LFSetupFPGAForADC(95, true);
while(!BUTTON_PRESS()) {
- // Configure to go in 125Khz listen mode
- SetupToAcquireRawAdcSamples(0);
-
WDT_HIT();
if (ledcontrol) LED_A_ON();
- DoAcquisition125k_internal(true);
+ DoAcquisition125k_internal(-1,true);
size = sizeof(BigBuf);
// FSK demodulator
size = fsk_demod(dest, size);
- WDT_HIT();
// we now have a set of cycle counts, loop over previous results and aggregate data into bit patterns
// 1->0 : fc/8 in sets of 6
idx+=sizeof(frame_marker_mask);
while(dest[idx] != dest[idx+1] && idx < size-2)
- { // Keep going until next frame marker (or error)
+ {
+ // Keep going until next frame marker (or error)
// Shift in a bit. Start by shifting high registers
hi2 = (hi2<<1)|(hi>>31);
hi = (hi<<1)|(lo>>31);
}
//Dbprintf("Num shifts: %d ", numshifts);
// Hopefully, we read a tag and hit upon the next frame marker
- if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
+ if(idx + sizeof(frame_marker_mask) < size)
{
- if (hi2 != 0){
- Dbprintf("TAG ID: %x%08x%08x (%d)",
- (unsigned int) hi2, (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
- }
- else {
- Dbprintf("TAG ID: %x%08x (%d)",
- (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
+ if ( memcmp(dest+idx, frame_marker_mask, sizeof(frame_marker_mask)) == 0)
+ {
+ if (hi2 != 0){
+ Dbprintf("TAG ID: %x%08x%08x (%d)",
+ (unsigned int) hi2, (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
+ }
+ else {
+ Dbprintf("TAG ID: %x%08x (%d)",
+ (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF);
+ }
}
+
}
// reset
size_t size=0, idx=0;
uint32_t code=0, code2=0;
+ // Configure to go in 125Khz listen mode
+ LFSetupFPGAForADC(95, true);
while(!BUTTON_PRESS()) {
- // Configure to go in 125Khz listen mode
- SetupToAcquireRawAdcSamples(0);
WDT_HIT();
if (ledcontrol) LED_A_ON();
- DoAcquisition125k_internal(true);
+ DoAcquisition125k_internal(-1,true);
size = sizeof(BigBuf);
// FSK demodulator
size = fsk_demod(dest, size);
- WDT_HIT();
// we now have a set of cycle counts, loop over previous results and aggregate data into bit patterns
// 1->0 : fc/8 in sets of 7
// Write one bit to card
void T55xxWriteBit(int bit)
{
+ FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
if (bit == 0)
SpinDelayUs(WRITE_0);
else
{
unsigned int i;
+ FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
// Give it a bit of time for the resonant antenna to settle.
// And for the tag to fully power up
// Now perform write (nominal is 5.6 ms for T55x7 and 18ms for E5550,
// so wait a little more)
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
SpinDelay(20);
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
}
uint8_t *dest = (uint8_t *)BigBuf;
int m=0, i=0;
+ FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
m = sizeof(BigBuf);
// Clear destination buffer before sending the command
memset(dest, 128, m);
LED_D_ON();
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
// Give it a bit of time for the resonant antenna to settle.
// And for the tag to fully power up
// Turn field on to read the response
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
// Now do the acquisition
i = 0;
uint8_t *dest = (uint8_t *)BigBuf;
int m=0, i=0;
+ FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
m = sizeof(BigBuf);
// Clear destination buffer before sending the command
memset(dest, 128, m);
LED_D_ON();
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
// Give it a bit of time for the resonant antenna to settle.
// And for the tag to fully power up
// Turn field on to read the response
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
// Now do the acquisition
i = 0;
for (bitidx = 0; i < GraphTraceLen; i++)
{
- if ( (GraphBuffer[i-1] > GraphBuffer[i] && dir == 1 && GraphBuffer[i] > lmax) || (GraphBuffer[i-1] < GraphBuffer[i] && dir == 0 && GraphBuffer[i] < lmin))
- {
- lc = i - lastval;
- lastval = i;
-
- // Switch depending on lc length:
- // Tolerance is 1/8 of clock rate (arbitrary)
- if (abs(lc-clock/4) < tolerance) {
- // 16T0
- if((i - pmc) == lc) { /* 16T0 was previous one */
- /* It's a PMC ! */
- i += (128+127+16+32+33+16)-1;
- lastval = i;
- pmc = 0;
- block_done = 1;
- }
- else {
- pmc = i;
- }
- } else if (abs(lc-clock/2) < tolerance) {
- // 32TO
- if((i - pmc) == lc) { /* 16T0 was previous one */
- /* It's a PMC ! */
- i += (128+127+16+32+33)-1;
- lastval = i;
- pmc = 0;
- block_done = 1;
- }
- else if(half_switch == 1) {
- BitStream[bitidx++] = 0;
- half_switch = 0;
- }
- else
- half_switch++;
- } else if (abs(lc-clock) < tolerance) {
- // 64TO
- BitStream[bitidx++] = 1;
- } else {
- // Error
- warnings++;
- if (warnings > 10)
- {
- Dbprintf("Error: too many detection errors, aborting.");
- return 0;
- }
- }
-
- if(block_done == 1) {
- if(bitidx == 128) {
- for(j=0; j<16; j++) {
- Blocks[num_blocks][j] = 128*BitStream[j*8+7]+
- 64*BitStream[j*8+6]+
- 32*BitStream[j*8+5]+
- 16*BitStream[j*8+4]+
- 8*BitStream[j*8+3]+
- 4*BitStream[j*8+2]+
- 2*BitStream[j*8+1]+
- BitStream[j*8];
- }
- num_blocks++;
- }
- bitidx = 0;
- block_done = 0;
- half_switch = 0;
- }
- if (GraphBuffer[i-1] > GraphBuffer[i]) dir=0;
- else dir = 1;
- }
- if(bitidx==255)
- bitidx=0;
- warnings = 0;
- if(num_blocks == 4) break;
+ if ( (GraphBuffer[i-1] > GraphBuffer[i] && dir == 1 && GraphBuffer[i] > lmax) || (GraphBuffer[i-1] < GraphBuffer[i] && dir == 0 && GraphBuffer[i] < lmin))
+ {
+ lc = i - lastval;
+ lastval = i;
+
+ // Switch depending on lc length:
+ // Tolerance is 1/8 of clock rate (arbitrary)
+ if (abs(lc-clock/4) < tolerance) {
+ // 16T0
+ if((i - pmc) == lc) { /* 16T0 was previous one */
+ /* It's a PMC ! */
+ i += (128+127+16+32+33+16)-1;
+ lastval = i;
+ pmc = 0;
+ block_done = 1;
+ }
+ else {
+ pmc = i;
+ }
+ } else if (abs(lc-clock/2) < tolerance) {
+ // 32TO
+ if((i - pmc) == lc) { /* 16T0 was previous one */
+ /* It's a PMC ! */
+ i += (128+127+16+32+33)-1;
+ lastval = i;
+ pmc = 0;
+ block_done = 1;
+ }
+ else if(half_switch == 1) {
+ BitStream[bitidx++] = 0;
+ half_switch = 0;
+ }
+ else
+ half_switch++;
+ } else if (abs(lc-clock) < tolerance) {
+ // 64TO
+ BitStream[bitidx++] = 1;
+ } else {
+ // Error
+ warnings++;
+ if (warnings > 10)
+ {
+ Dbprintf("Error: too many detection errors, aborting.");
+ return 0;
+ }
+ }
+
+ if(block_done == 1) {
+ if(bitidx == 128) {
+ for(j=0; j<16; j++) {
+ Blocks[num_blocks][j] = 128*BitStream[j*8+7]+
+ 64*BitStream[j*8+6]+
+ 32*BitStream[j*8+5]+
+ 16*BitStream[j*8+4]+
+ 8*BitStream[j*8+3]+
+ 4*BitStream[j*8+2]+
+ 2*BitStream[j*8+1]+
+ BitStream[j*8];
+ }
+ num_blocks++;
+ }
+ bitidx = 0;
+ block_done = 0;
+ half_switch = 0;
+ }
+ if(i < GraphTraceLen)
+ {
+ if (GraphBuffer[i-1] > GraphBuffer[i]) dir=0;
+ else dir = 1;
+ }
+ }
+ if(bitidx==255)
+ bitidx=0;
+ warnings = 0;
+ if(num_blocks == 4) break;
}
memcpy(outBlocks, Blocks, 16*num_blocks);
return num_blocks;
LED_D_ON();
//Field on
+ FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);
// Give it a bit of time for the resonant antenna to settle.
// And for the tag to fully power up
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
SpinDelayUs(55*8); //55 cycles off (8us each)for 4305
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);//field on
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);//field on
SpinDelayUs(16*8); //16 cycles on (8us each)
// now start writting
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
SpinDelayUs(23*8); //16-4 cycles off (8us each)
FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
- FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);//field on
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | FPGA_LF_ADC_READER_FIELD);//field on
SpinDelayUs(9*8); //16 cycles on (8us each)
}
}