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just in case psk get odd clocks in some old system

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iceman1001 2023-07-22 23:27:30 +02:00
commit 8e38723149
1 changed files with 9 additions and 7 deletions
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14
common/lfdemod.c
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@ -1118,10 +1118,12 @@ uint16_t countFC(const uint8_t *bits, size_t size, bool fskAdj) {
fcH = fcLens[best2]; fcH = fcLens[best2];
fcL = fcLens[best1]; fcL = fcLens[best1];
} }
/*
if ((size - 180) / fcH / 3 > fcCnts[best1] + fcCnts[best2]) { if ((size - 180) / fcH / 3 > fcCnts[best1] + fcCnts[best2]) {
if (g_debugMode == 2) prnt("DEBUG countfc: fc is too large: %zu > %u. Not psk or fsk", (size - 180) / fcH / 3, fcCnts[best1] + fcCnts[best2]); if (g_debugMode == 2) prnt("DEBUG countfc: fc is too large: %zu > %u. Not psk or fsk", (size - 180) / fcH / 3, fcCnts[best1] + fcCnts[best2]);
return 0; //lots of waves not psk or fsk return 0; //lots of waves not psk or fsk
} }
*/
// TODO: take top 3 answers and compare to known Field clocks to get top 2 // TODO: take top 3 answers and compare to known Field clocks to get top 2
uint16_t fcs = (((uint16_t)fcH) << 8) | fcL; uint16_t fcs = (((uint16_t)fcH) << 8) | fcL;
@ -1132,7 +1134,7 @@ uint16_t countFC(const uint8_t *bits, size_t size, bool fskAdj) {
// detect psk clock by reading each phase shift // detect psk clock by reading each phase shift
// a phase shift is determined by measuring the sample length of each wave // a phase shift is determined by measuring the sample length of each wave
int DetectPSKClock(uint8_t *dest, size_t size, int clock, size_t *firstPhaseShift, uint8_t *curPhase, uint8_t *fc) { int DetectPSKClock(uint8_t *dest, size_t size, int clock, size_t *firstPhaseShift, uint8_t *curPhase, uint8_t *fc) {
uint8_t clk[] = {255, 16, 32, 40, 50, 64, 100, 128, 255}; //255 is not a valid clock uint16_t clk[] = {255, 16, 32, 40, 50, 64, 100, 128, 256, 272, 384}; // 255 is not a valid clock
uint16_t loopCnt = 4096; // don't need to loop through entire array... uint16_t loopCnt = 4096; // don't need to loop through entire array...
if (size < 160 + 20) return 0; if (size < 160 + 20) return 0;
@ -1154,8 +1156,8 @@ int DetectPSKClock(uint8_t *dest, size_t size, int clock, size_t *firstPhaseShif
uint8_t clkCnt; uint8_t clkCnt;
uint16_t waveLenCnt, fullWaveLen = 0; uint16_t waveLenCnt, fullWaveLen = 0;
uint16_t bestErr[] = {1000, 1000, 1000, 1000, 1000, 1000, 1000, 1000, 1000}; uint16_t bestErr[] = {1000, 1000, 1000, 1000, 1000, 1000, 1000, 1000, 1000, 1000, 1000};
uint16_t peaksdet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0}; uint16_t peaksdet[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
//find start of modulating data in trace //find start of modulating data in trace
size_t i = findModStart(dest, size, *fc); size_t i = findModStart(dest, size, *fc);
@ -1177,7 +1179,7 @@ int DetectPSKClock(uint8_t *dest, size_t size, int clock, size_t *firstPhaseShif
} }
//test each valid clock from greatest to smallest to see which lines up //test each valid clock from greatest to smallest to see which lines up
for (clkCnt = 7; clkCnt >= 1 ; clkCnt--) { for (clkCnt = 9; clkCnt >= 1 ; clkCnt--) {
uint8_t tol = *fc / 2; uint8_t tol = *fc / 2;
size_t lastClkBit = firstFullWave; //set end of wave as clock align size_t lastClkBit = firstFullWave; //set end of wave as clock align
size_t waveStart = 0; size_t waveStart = 0;
@ -1217,8 +1219,8 @@ int DetectPSKClock(uint8_t *dest, size_t size, int clock, size_t *firstPhaseShif
} }
//all tested with errors //all tested with errors
//return the highest clk with the most peaks found //return the highest clk with the most peaks found
uint8_t best = 7; uint8_t best = 9;
for (i = 7; i >= 1; i--) { for (i = 9; i >= 1; i--) {
if (peaksdet[i] > peaksdet[best]) if (peaksdet[i] > peaksdet[best])
best = i; best = i;