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fix #1175 - biphase demod identification of value clocks now fails if no changes detected

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iceman1001 2021-01-28 00:35:14 +01:00
commit 02c1034caa
1 changed files with 23 additions and 5 deletions
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28
common/lfdemod.c
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@ -41,6 +41,8 @@
#include <stdlib.h> // qsort #include <stdlib.h> // qsort
#include "parity.h" // for parity test #include "parity.h" // for parity test
#include "pm3_cmd.h" // error codes #include "pm3_cmd.h" // error codes
#include "commonutil.h" // Arraylen
// ********************************************************************************************** // **********************************************************************************************
// ---------------------------------Utilities Section-------------------------------------------- // ---------------------------------Utilities Section--------------------------------------------
// ********************************************************************************************** // **********************************************************************************************
@ -770,6 +772,22 @@ int DetectASKClock(uint8_t *dest, size_t size, int *clock, int maxErr) {
//if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, # Errors %d, Current Best Clk %d, bestStart %d", clk[k], bestErr[k], clk[best], bestStart[best]); //if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, # Errors %d, Current Best Clk %d, bestStart %d", clk[k], bestErr[k], clk[best], bestStart[best]);
} }
bool chg = false;
for (i = 0; i < ARRAYLEN(bestErr); i++) {
chg = (bestErr[i] != 1000);
if (chg)
break;
chg = (bestStart[i] != 0);
if (chg)
break;
}
// just noise - no super good detection. good enough
if (chg == false) {
if (g_debugMode == 2) prnt("DEBUG DetectASKClock: no good values detected - aborting");
return -2;
}
if (!found_clk) if (!found_clk)
*clock = clk[best]; *clock = clk[best];
@ -1671,12 +1689,12 @@ int askdemod_ext(uint8_t *bits, size_t *size, int *clk, int *invert, int maxErr,
*startIdx = start - (*clk / 2); *startIdx = start - (*clk / 2);
if (g_debugMode == 2) prnt("DEBUG: (askdemod_ext) Weak wave detected: startIdx %i", *startIdx); if (g_debugMode == 2) prnt("DEBUG: (askdemod_ext) Weak wave detected: startIdx %i", *startIdx);
int lastBit; //set first clock check - can go negative int lastBit; // set first clock check - can go negative
size_t i, bitnum = 0; //output counter size_t i, bitnum = 0; // output counter
uint8_t midBit = 0; uint8_t midBit = 0;
uint8_t tol = 0; //clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave uint8_t tol = 0; // clock tolerance adjust - waves will be accepted as within the clock if they fall + or - this value + clock from last valid wave
if (*clk <= 32) tol = 1; //clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely if (*clk <= 32) tol = 1; // clock tolerance may not be needed anymore currently set to + or - 1 but could be increased for poor waves or removed entirely
size_t MaxBits = 3072; //max bits to collect size_t MaxBits = 3072; // max bits to collect
lastBit = start - *clk; lastBit = start - *clk;
for (i = start; i < *size; ++i) { for (i = start; i < *size; ++i) {