ADD: @marshmellows fixes for t55x7 reading signal.

[proxmark3-svn] / armsrc / lfsampling.c

diff --git a/armsrc/lfsampling.c b/armsrc/lfsampling.c
index 635934ef64fee23bf631c3f7c53c5902df239dab..339434215512a7e9536dc9d19a371b14857a7dde 100644 (file)
--- a/armsrc/lfsampling.c
+++ b/armsrc/lfsampling.c
@@ -245,7 +245,60 @@ uint32_t SampleLF(bool printCfg)
 * @return number of bits sampled
 **/
 
-uint32_t SnoopLF()
-{
+uint32_t SnoopLF() {
        return ReadLF(false, true);
 }
+
+/**
+* acquisition of T55x7 LF signal. Similart to other LF, but adjusted with @marshmellows thresholds
+* the data is collected in BigBuf.
+**/
+void doT55x7Acquisition(void){
+
+       #define T55xx_SAMPLES_SIZE 12000 // 32 x 32 x 10  (32 bit times numofblock (7), times clock skip..)
+       #define T55xx_READ_UPPER_THRESHOLD 128+40  // 50
+       #define T55xx_READ_TOL   5
+       //#define T55xx_READ_LOWER_THRESHOLD 128-40  //-50
+
+       uint8_t *dest = BigBuf_get_addr();
+       uint16_t bufsize = BigBuf_max_traceLen();
+       
+       if ( bufsize > T55xx_SAMPLES_SIZE )
+               bufsize = T55xx_SAMPLES_SIZE;
+
+       memset(dest, 0, bufsize);
+               
+       uint16_t i = 0;
+       bool startFound = false;
+       bool highFound = false;
+       uint8_t curSample = 0;
+       uint8_t firstSample = 0;
+       for(;;) {
+               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) {
+                       curSample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+                       
+                       // find first high sample
+                       if (!startFound && curSample > T55xx_READ_UPPER_THRESHOLD) {
+                               if (curSample > firstSample) 
+                                       firstSample = curSample;
+                               highFound = true;
+                       } else if (!highFound) {
+                               continue;
+                       }
+
+                       // skip until samples begin to change
+                       if (startFound || curSample < firstSample-T55xx_READ_TOL){
+                               if (!startFound) 
+                                       dest[i++] = firstSample;
+                               startFound = true;
+                               dest[i++] = curSample;
+                       LED_D_OFF();
+                       if (i >= bufsize) break;
+                       }
+               }
+       }
+}
\ No newline at end of file