#include "lfsampling.h"
+/*
+Default LF config is set to:
+ decimation = 1 (we keep 1 out of 1 samples)
+ bits_per_sample = 8
+ averaging = YES
+ divisor = 95 (125khz)
+ trigger_threshold = 0
+ */
sample_config config = { 1, 8, 1, 95, 0 } ;
void printConfig() {
Dbprintf("LF Sampling config: ");
- Dbprintf(" [q] divisor: %d ", config.divisor);
+ Dbprintf(" [q] divisor: %d (%d KHz)", config.divisor, 12000 / (config.divisor+1));
Dbprintf(" [b] bps: %d ", config.bits_per_sample);
Dbprintf(" [d] decimation: %d ", config.decimation);
- Dbprintf(" [a] averaging: %d ", config.averaging);
+ Dbprintf(" [a] averaging: %s ", (config.averaging) ? "Yes" : "No");
Dbprintf(" [t] trigger threshold: %d ", config.trigger_threshold);
}
-
/**
* Called from the USB-handler to set the sampling configuration
* The sampling config is used for std reading and snooping.
void setSamplingConfig(sample_config *sc) {
if(sc->divisor != 0) config.divisor = sc->divisor;
if(sc->bits_per_sample != 0) config.bits_per_sample = sc->bits_per_sample;
- if(sc->decimation != 0) config.decimation = sc->decimation;
if(sc->trigger_threshold != -1) config.trigger_threshold = sc->trigger_threshold;
-
+
+ config.decimation = (sc->decimation != 0) ? sc->decimation : 1;
config.averaging = sc->averaging;
if(config.bits_per_sample > 8) config.bits_per_sample = 8;
- if(config.decimation < 1) config.decimation = 1;
printConfig();
}
* @param silent - is true, now outputs are made. If false, dbprints the status
* @return the number of bits occupied by the samples.
*/
-uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averaging, int trigger_threshold,bool silent) {
+uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averaging, int trigger_threshold, bool silent) {
//bigbuf, to hold the aquired raw data signal
uint8_t *dest = BigBuf_get_addr();
uint16_t bufsize = BigBuf_max_traceLen();
* @return number of bits sampled
**/
uint32_t SampleLF(bool printCfg) {
- return ReadLF(true, printCfg);
+ BigBuf_Clear_ext(false);
+ uint32_t ret = ReadLF(true, printCfg);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+ return ret;
}
/**
* Initializes the FPGA for snoop-mode (field off), and acquires the samples.
* @return number of bits sampled
**/
uint32_t SnoopLF() {
- return ReadLF(false, true);
+ BigBuf_Clear_ext(false);
+ uint32_t ret = ReadLF(false, true);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+ return ret;
}
/**
}
}
}
-
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+/**
+* acquisition of Cotag LF signal. Similart to other LF, since the Cotag has such long datarate RF/384
+* and is Manchester?, we directly gather the manchester data into bigbuff
+**/
+
+#define COTAG_T1 384
+#define COTAG_T2 (COTAG_T1>>1)
+#define COTAG_ONE_THRESHOLD 128+30
+#define COTAG_ZERO_THRESHOLD 128-30
+void doCotagAcquisition(size_t sample_size) {
+
+ uint8_t *dest = BigBuf_get_addr();
+ uint16_t bufsize = BigBuf_max_traceLen();
+
+ if ( bufsize > sample_size )
+ bufsize = sample_size;
+
+ dest[0] = 0;
+ uint8_t sample = 0, firsthigh = 0, firstlow = 0;
+ uint16_t i = 0;
+
+ while (!BUTTON_PRESS() && !usb_poll_validate_length() && (i < bufsize) ) {
+ WDT_HIT();
+ if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
+ AT91C_BASE_SSC->SSC_THR = 0x43;
+ LED_D_ON();
+ }
+
+ if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
+ sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+ LED_D_OFF();
+
+ // find first peak
+ if ( !firsthigh ) {
+ if (sample < COTAG_ONE_THRESHOLD)
+ continue;
+ firsthigh = 1;
+ }
+ if ( !firstlow ){
+ if (sample > COTAG_ZERO_THRESHOLD )
+ continue;
+ firstlow = 1;
+ }
+
+ ++i;
+
+ if ( sample > COTAG_ONE_THRESHOLD)
+ dest[i] = 255;
+ else if ( sample < COTAG_ZERO_THRESHOLD)
+ dest[i] = 0;
+ else
+ dest[i] = dest[i-1];
+ }
+ }
+}
+
+uint32_t doCotagAcquisitionManchester() {
+
+ uint8_t *dest = BigBuf_get_addr();
+ uint16_t bufsize = BigBuf_max_traceLen();
+
+ if ( bufsize > COTAG_BITS )
+ bufsize = COTAG_BITS;
+
+ dest[0] = 0;
+ uint8_t sample = 0, firsthigh = 0, firstlow = 0;
+ uint16_t sample_counter = 0, period = 0;
+ uint8_t curr = 0, prev = 0;
+
+ while (!BUTTON_PRESS() && !usb_poll_validate_length() && (sample_counter < bufsize) ) {
+ WDT_HIT();
+ if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
+ AT91C_BASE_SSC->SSC_THR = 0x43;
+ LED_D_ON();
+ }
+
+ if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
+ sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+ LED_D_OFF();
+
+ // find first peak
+ if ( !firsthigh ) {
+ if (sample < COTAG_ONE_THRESHOLD)
+ continue;
+ firsthigh = 1;
+ }
+
+ if ( !firstlow ){
+ if (sample > COTAG_ZERO_THRESHOLD )
+ continue;
+ firstlow = 1;
+ }
+
+ // set sample 255, 0, or previous
+ if ( sample > COTAG_ONE_THRESHOLD){
+ prev = curr;
+ curr = 1;
+ }
+ else if ( sample < COTAG_ZERO_THRESHOLD) {
+ prev = curr;
+ curr = 0;
+ }
+ else {
+ curr = prev;
+ }
+
+ // full T1 periods,
+ if ( period > 0 ) {
+ --period;
+ continue;
+ }
+
+ dest[sample_counter] = curr;
+ ++sample_counter;
+ period = COTAG_T1;
+ }
+ }
+ return sample_counter;
+}
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