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fix: askdemod - enhances which solves some viking demod errors

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This commit is contained in:
iceman1001 2019-05-25 13:27:43 -04:00
commit 37c30c0395
5 changed files with 55 additions and 45 deletions
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39
common/lfdemod.c
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@ -315,10 +315,10 @@ static int getClosestClock(int testclk) {
uint16_t clocks[] = {8, 16, 32, 40, 50, 64, 100, 128, 256, 384};
uint8_t limit[] = {1, 2, 4, 4, 5, 8, 8, 8, 8, 8};
for (uint8_t i = 0; i < 10; i++)
for (uint8_t i = 0; i < 10; i++) {
if (testclk >= clocks[i] - limit[i] && testclk <= clocks[i] + limit[i])
return clocks[i];
}
return 0;
}
@ -480,17 +480,19 @@ bool DetectCleanAskWave(uint8_t *dest, size_t size, uint8_t high, uint8_t low) {
// by marshmellow
// to help detect clocks on heavily clipped samples
// based on count of low to low
int DetectStrongAskClock(uint8_t *dest, size_t size, int high, int low, int *clock) {
int DetectStrongAskClock(uint8_t *src, size_t size, int high, int low, int *clock) {
size_t i = 100;
size_t minClk = 512;
uint16_t shortestWaveIdx = 0;
// get to first full low to prime loop and skip incomplete first pulse
getNextHigh(dest, size, high, &i);
getNextLow(dest, size, low, &i);
getNextHigh(src, size, high, &i);
getNextLow(src, size, low, &i);
if (i == size)
return -1;
if (size < 512)
return -2;
// clock, numoftimes, first idx
uint16_t tmpclk[10][3] = {
@ -507,12 +509,12 @@ int DetectStrongAskClock(uint8_t *dest, size_t size, int high, int low, int *clo
};
// loop through all samples (well, we don't want to go out-of-bounds)
while (i < size - 512) {
while (i < (size - 512)) {
// measure from low to low
size_t startwave = i;
getNextHigh(dest, size, high, &i);
getNextLow(dest, size, low, &i);
getNextHigh(src, size, high, &i);
getNextLow(src, size, low, &i);
//get minimum measured distance
if (i - startwave < minClk && i < size) {
@ -1401,17 +1403,18 @@ int BiphaseRawDecode(uint8_t *bits, size_t *size, int *offset, int invert) {
//take 10 and 01 and manchester decode
//run through 2 times and take least errCnt
// "," indicates 00 or 11 wrong bit
int manrawdecode(uint8_t *bits, size_t *size, uint8_t invert, uint8_t *alignPos) {
uint16_t manrawdecode(uint8_t *bits, size_t *size, uint8_t invert, uint8_t *alignPos) {
// sanity check
if (*size < 16) return -1;
if (*size < 16) return 0xFFFF;
int errCnt = 0, bestErr = 1000;
uint16_t bitnum = 0, maxBits = 512, bestRun = 0;
size_t i, k;
//find correct start position [alignment]
for (k = 0; k < 2; ++k) {
for (k = 0; k < 2; k++) {
for (i = k; i < *size - 1; i += 2) {
if (bits[i] == bits[i + 1])
@ -1431,7 +1434,7 @@ int manrawdecode(uint8_t *bits, size_t *size, uint8_t invert, uint8_t *alignPos)
*alignPos = bestRun;
//decode
for (i = bestRun; i < *size - 1; i += 2) {
for (i = bestRun; i < *size; i += 2) {
if (bits[i] == 1 && (bits[i + 1] == 0)) {
bits[bitnum++] = invert;
} else if ((bits[i] == 0) && bits[i + 1] == 1) {
@ -1448,7 +1451,7 @@ int manrawdecode(uint8_t *bits, size_t *size, uint8_t invert, uint8_t *alignPos)
//by marshmellow
//demodulates strong heavily clipped samples
//RETURN: num of errors. if 0, is ok.
static int cleanAskRawDemod(uint8_t *bits, size_t *size, int clk, int invert, int high, int low, int *startIdx) {
static uint16_t cleanAskRawDemod(uint8_t *bits, size_t *size, int clk, int invert, int high, int low, int *startIdx) {
*startIdx = 0;
size_t bitCnt = 0, smplCnt = 1, errCnt = 0, pos = 0;
uint8_t cl_4 = clk / 4;
@ -1463,7 +1466,8 @@ static int cleanAskRawDemod(uint8_t *bits, size_t *size, int clk, int invert, in
smplCnt++;
} else if (bits[i] <= low && !waveHigh) {
smplCnt++;
} else { //transition
} else {
//transition
if ((bits[i] >= high && !waveHigh) || (bits[i] <= low && waveHigh)) {
// 8 :: 8-2-1 = 5 8+2+1 = 11
@ -1472,7 +1476,8 @@ static int cleanAskRawDemod(uint8_t *bits, size_t *size, int clk, int invert, in
// 64 :: 64-16-1 = 47 64+16+1 = 81
if (smplCnt > clk - cl_4 - 1) { //full clock
if (smplCnt > clk + cl_4 + 1) { //too many samples
if (smplCnt > clk + cl_4 + 1) {
//too many samples
errCnt++;
if (g_debugMode == 2) prnt("DEBUG ASK: cleanAskRawDemod ASK Modulation Error FULL at: %u [%u > %u]", i, smplCnt, clk + cl_4 + 1);
bits[bitCnt++] = 7;
@ -1515,6 +1520,7 @@ static int cleanAskRawDemod(uint8_t *bits, size_t *size, int clk, int invert, in
}
}
}
*size = bitCnt;
if (*startIdx < 0)
@ -1823,6 +1829,7 @@ static size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t clk, uint8_t in
}
memset(dest + numBits, dest[i - 1] ^ invert, n);
numBits += n;
if (g_debugMode == 2) prnt("DEBUG (aggregate_bits) extra bits in the end");
}
return numBits;
}
@ -1833,7 +1840,9 @@ size_t fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8
if (signalprop.isnoise) return 0;
// FSK demodulator
size = fsk_wave_demod(dest, size, fchigh, fclow, start_idx);
if (g_debugMode == 2) prnt("DEBUG (fskdemod) got %zu bits", size);
size = aggregate_bits(dest, size, rfLen, invert, fchigh, fclow, start_idx);
if (g_debugMode == 2) prnt("DEBUG (fskdemod) got %zu bits", size);
return size;
}

2
common/lfdemod.h
View file

@ -66,7 +66,7 @@ size_t fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uin
void getHiLo(int *high, int *low, uint8_t fuzzHi, uint8_t fuzzLo);
uint32_t manchesterEncode2Bytes(uint16_t datain);
int ManchesterEncode(uint8_t *bits, size_t size);
int manrawdecode(uint8_t *bits, size_t *size, uint8_t invert, uint8_t *alignPos);
uint16_t manrawdecode(uint8_t *bits, size_t *size, uint8_t invert, uint8_t *alignPos);
int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int *startIdx);
bool parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType);
bool preambleSearch(uint8_t *bits, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx);