]> git.zerfleddert.de Git - proxmark3-svn/blobdiff - armsrc/lfsampling.c
Legic: rewrite reader to use xcorrelation and precise timing (#654)
[proxmark3-svn] / armsrc / lfsampling.c
index 138814b7e0a40986a5302bd355b9707a814067e5..3b0762653b7ea99ea2e1b2dcc1d01632e3dd08db 100644 (file)
 #include "apps.h"
 #include "util.h"
 #include "string.h"
-
 #include "lfsampling.h"
+#include "usb_cdc.h"   // for usb_poll_validate_length
+//#include "ticks.h"           // for StartTicks
 
 sample_config config = { 1, 8, 1, 95, 0 } ;
 
 void printConfig()
 {
-       Dbprintf("Sampling config: ");
+       Dbprintf("LF Sampling config: ");
        Dbprintf("  [q] divisor:           %d ", config.divisor);
        Dbprintf("  [b] bps:               %d ", config.bits_per_sample);
        Dbprintf("  [d] decimation:        %d ", config.decimation);
@@ -62,7 +63,6 @@ typedef struct {
        uint32_t position;
 } BitstreamOut;
 
-
 /**
  * @brief Pushes bit onto the stream
  * @param stream
@@ -104,7 +104,6 @@ void LFSetupFPGAForADC(int divisor, bool lf_field)
        FpgaSetupSsc();
 }
 
-
 /**
  * Does the sample acquisition. If threshold is specified, the actual sampling
  * is not commenced until the threshold has been reached.
@@ -120,14 +119,13 @@ void LFSetupFPGAForADC(int divisor, bool lf_field)
  * @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, int bufsize, int cancel_after)
 {
        //.
        uint8_t *dest = BigBuf_get_addr();
-    int bufsize = BigBuf_max_traceLen();
+       bufsize = (bufsize > 0 && bufsize < BigBuf_max_traceLen()) ? bufsize : BigBuf_max_traceLen();
 
-       memset(dest, 0, bufsize);
+       //memset(dest, 0, bufsize); //creates issues with cmdread (marshmellow)
 
        if(bits_per_sample < 1) bits_per_sample = 1;
        if(bits_per_sample > 8) bits_per_sample = 8;
@@ -142,8 +140,9 @@ uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averag
        uint32_t sample_sum =0 ;
        uint32_t sample_total_numbers =0 ;
        uint32_t sample_total_saved =0 ;
+       uint32_t cancel_counter = 0;
 
-       while(!BUTTON_PRESS()) {
+       while(!BUTTON_PRESS() && !usb_poll_validate_length() ) {
                WDT_HIT();
                if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
                        AT91C_BASE_SSC->SSC_THR = 0x43;
@@ -152,9 +151,14 @@ uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averag
                if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
                        sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
                        LED_D_OFF();
-                       if (trigger_threshold > 0 && sample < trigger_threshold)
+                       // threshold either high or low values 128 = center 0.  if trigger = 178 
+                       if ((trigger_threshold > 0) && (sample < (trigger_threshold+128)) && (sample > (128-trigger_threshold))) { // 
+                               if (cancel_after > 0) {
+                                       cancel_counter++;
+                                       if (cancel_after == cancel_counter) break;
+                               }
                                continue;
-
+                       }
                        trigger_threshold = 0;
                        sample_total_numbers++;
 
@@ -214,32 +218,40 @@ uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averag
  */
 uint32_t DoAcquisition_default(int trigger_threshold, bool silent)
 {
-       return DoAcquisition(1,8,0,trigger_threshold,silent);
+       return DoAcquisition(1,8,0,trigger_threshold,silent,0,0);
 }
-uint32_t DoAcquisition_config( bool silent)
+uint32_t DoAcquisition_config(bool silent, int sample_size)
 {
        return DoAcquisition(config.decimation
                                  ,config.bits_per_sample
                                  ,config.averaging
                                  ,config.trigger_threshold
-                                 ,silent);
+                                 ,silent
+                                 ,sample_size
+                                 ,0);
+}
+
+uint32_t DoPartialAcquisition(int trigger_threshold, bool silent, int sample_size, int cancel_after) {
+       return DoAcquisition(1,8,0,trigger_threshold,silent,sample_size,cancel_after);
 }
 
-uint32_t ReadLF(bool activeField)
+uint32_t ReadLF(bool activeField, bool silent, int sample_size)
 {
-       printConfig();
+       if (!silent) printConfig();
        LFSetupFPGAForADC(config.divisor, activeField);
        // Now call the acquisition routine
-       return DoAcquisition_config(false);
+       return DoAcquisition_config(silent, sample_size);
 }
 
 /**
 * Initializes the FPGA for reader-mode (field on), and acquires the samples.
 * @return number of bits sampled
 **/
-uint32_t SampleLF()
+uint32_t SampleLF(bool printCfg, int sample_size)
 {
-       return ReadLF(true);
+       uint32_t ret = ReadLF(true, printCfg, sample_size);
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+       return ret;
 }
 /**
 * Initializes the FPGA for snoop-mode (field off), and acquires the samples.
@@ -248,5 +260,135 @@ uint32_t SampleLF()
 
 uint32_t SnoopLF()
 {
-       return ReadLF(false);
+       uint32_t ret = ReadLF(false, true, 0);
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+       return ret;
+}
+
+/**
+* acquisition of Cotag LF signal. Similar 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
+#ifndef COTAG_BITS
+#define COTAG_BITS 264
+#endif
+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;
+       uint16_t noise_counter = 0;
+       while (!BUTTON_PRESS() && !usb_poll_validate_length() && (sample_counter < bufsize) && (noise_counter < (COTAG_T1<<1)) ) {
+               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) {
+                                       noise_counter++;
+                                       continue;
+                               }
+                               noise_counter = 0;
+                               firsthigh = 1;
+                       }
+
+                       if ( !firstlow ){
+                               if (sample > COTAG_ZERO_THRESHOLD ) {
+                                       noise_counter++;
+                                       continue;
+                               }
+                               noise_counter=0;
+                               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;
 }
Impressum, Datenschutz