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chg: cleaning up in lfdemod.c, currently the ASK clock, demod of strong and weak signals

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Chris 2018-11-07 12:21:57 +01:00
parent 16929bad69
commit c75c0e4e52
1 changed files with 75 additions and 51 deletions
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126
common/lfdemod.c
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@ -322,7 +322,7 @@ size_t findModStart(uint8_t *src, size_t size, uint8_t expWaveSize) {
uint8_t thresholdCnt = 0;
bool isAboveThreshold = src[i++] >= signalprop.mean; //FSK_PSK_THRESHOLD;
for (; i < size-20; i++ ) {
if(src[i] < signalprop.mean && isAboveThreshold) {
if (src[i] < signalprop.mean && isAboveThreshold) {
thresholdCnt++;
if (thresholdCnt > 2 && waveSizeCnt < expWaveSize+1) break;
isAboveThreshold = false;
@ -341,20 +341,12 @@ size_t findModStart(uint8_t *src, size_t size, uint8_t expWaveSize) {
return i;
}
// iceman: ranges the old defintion, becomes very forgiving when clock speed increase.
// clocks[i] - (clocks[i]/8) && testclk <= clocks[i]+1 )
// 8 (7-9)
// 16 (14-17)
// 32 (28-33)
// 40 (35-41)
// 50 (46-51)
// 64 (56-65)
// 128 (112-129)
int getClosestClock(int testclk) {
uint8_t clocks[] = {8,16,32,40,50,64,128};
uint16_t clocks[] = {8, 16, 32, 40, 50, 64, 128, 256, 384};
uint8_t limit[] = {1, 2, 4, 4, 5, 8, 8, 8, 8};
for (uint8_t i = 0; i < 7; i++)
if ( testclk >= clocks[i]-2 && testclk <= clocks[i]+1 )
for (uint8_t i = 0; i < 9; i++)
if ( testclk >= clocks[i]-limit[i] && testclk <= clocks[i]+limit[i] )
return clocks[i];
return 0;
@ -543,8 +535,9 @@ int DetectStrongAskClock(uint8_t *dest, size_t size, int high, int low, int *clo
// set clock
if (g_debugMode == 2) prnt("DEBUG ASK: DetectStrongAskClock smallest wave: %d", minClk);
*clock = getClosestClock(minClk);
if (*clock == 0)
return 0;
return -1;
return shortestWaveIdx;
}
@ -554,43 +547,60 @@ int DetectStrongAskClock(uint8_t *dest, size_t size, int high, int low, int *clo
// maybe somehow adjust peak trimming value based on samples to fix?
// return start index of best starting position for that clock and return clock (by reference)
int DetectASKClock(uint8_t *dest, size_t size, int *clock, int maxErr) {
size_t i = 1;
uint16_t clk[] = {255,8,16,32,40,50,64,100,128,255};
uint16_t clkEnd = 9;
uint16_t loopCnt = 1500; //don't need to loop through entire array... (cotag has clock of 384)
if (size <= loopCnt + 60) return -1; //not enough samples
size -= 60; //sometimes there is a strange end wave - filter out this....
//if we already have a valid clock
uint8_t clockFnd = 0;
for (; i < clkEnd; ++i) {
if (clk[i] == *clock) {
//clock found but continue to find best startpos
clockFnd = i;
}
}
//don't need to loop through entire array. (cotag has clock of 384)
uint16_t loopCnt = 1500;
// not enough samples
if (size <= loopCnt + 60){
if (g_debugMode == 2) prnt("DEBUG DetectASKClock: not enough samples - aborting");
return -1;
}
// just noise - no super good detection. good enough
if (signalprop.isnoise) {
if (g_debugMode == 2) prnt("DEBUG DetectASKClock: just noise detected - aborting");
return -1;
return -2;
}
//get high and low peak
size_t i = 1;
uint16_t num_clks = 9;
// first 255 value pos0 is placeholder for user inputed clock.
uint16_t clk[] = {255, 8, 16, 32, 40, 50, 64, 100, 128, 255};
// sometimes there is a strange end wave - filter out this
size -= 60;
// What is purpose?
// already have a valid clock?
uint8_t found_clk = 0;
for (; i < num_clks; ++i) {
if (clk[i] == *clock) {
found_clk = i;
}
}
// threshold 75% of high, low peak
int peak_hi, peak_low;
getHiLo(&peak_hi, &peak_low, 75, 75);
//test for large clean peaks
if (!clockFnd){
// test for large clean, STRONG, CLIPPED peaks
if (!found_clk) {
if (DetectCleanAskWave(dest, size, peak_hi, peak_low)){
int idx = DetectStrongAskClock(dest, size, peak_hi, peak_low, clock);
if (g_debugMode == 2)
prnt("DEBUG ASK: detectaskclk Clean Ask Wave Detected: clk %i, Best Starting Position: %i", *clock, idx);
if (idx > 0)
return idx; //return shortest wave start position
prnt("DEBUG ASK: DetectASKClock Clean ASK Wave detected: clk %i, Best Starting Position: %i", *clock, idx);
// return shortest wave start position
if (idx > -1)
return idx;
}
}
// test for weak peaks
// test clock if given as cmd parameter
if ( *clock > 0 )
clk[0] = *clock;
@ -601,15 +611,15 @@ int DetectASKClock(uint8_t *dest, size_t size, int *clock, int maxErr) {
uint8_t bestStart[] = {0,0,0,0,0,0,0,0,0};
size_t errCnt = 0, arrLoc, loopEnd;
if (clockFnd > 0) {
clkCnt = clockFnd;
clkEnd = clockFnd+1;
if (found_clk) {
clkCnt = found_clk;
num_clks = found_clk + 1;
} else {
clkCnt = 1;
}
//test each valid clock from smallest to greatest to see which lines up
for (; clkCnt < clkEnd; clkCnt++) {
for (; clkCnt < num_clks; clkCnt++) {
if (clk[clkCnt] <= 32) {
tol = 1;
} else {
@ -640,15 +650,15 @@ int DetectASKClock(uint8_t *dest, size_t size, int *clock, int maxErr) {
errCnt++;
}
}
//if we found no errors then we can stop here and a low clock (common clocks)
// if we found no errors then we can stop here and a low clock (common clocks)
// this is correct one - return this clock
//if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, err %d, startpos %d, endpos %d", clk[clkCnt], errCnt, j, i);
// if (g_debugMode == 2) prnt("DEBUG ASK: clk %d, err %d, startpos %d, endpos %d", clk[clkCnt], errCnt, j, i);
if (errCnt == 0 && clkCnt < 7) {
if (!clockFnd)
if (!found_clk)
*clock = clk[clkCnt];
return j;
}
//if we found errors see if it is lowest so far and save it as best run
// if we found errors see if it is lowest so far and save it as best run
if (errCnt < bestErr[clkCnt]) {
bestErr[clkCnt] = errCnt;
bestStart[clkCnt] = j;
@ -658,7 +668,7 @@ int DetectASKClock(uint8_t *dest, size_t size, int *clock, int maxErr) {
uint8_t k, best = 0;
for (k=1; k < clkEnd; ++k){
for (k=1; k < num_clks; ++k){
if (bestErr[k] < bestErr[best]){
if (bestErr[k] == 0) bestErr[k] = 1;
// current best bit to error ratio vs new bit to error ratio
@ -668,7 +678,9 @@ 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 (!clockFnd) *clock = clk[best];
if (!found_clk)
*clock = clk[best];
return bestStart[best];
}
@ -1419,14 +1431,14 @@ int manrawdecode(uint8_t *bits, size_t *size, uint8_t invert, uint8_t *alignPos)
int 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;
uint8_t cl_2 = clk / 2;
getNextHigh(bits, *size, high, &pos);
bool waveHigh = true;
for (size_t i=pos; i < *size; i++){
getNextHigh(bits, *size, high, &pos);
// sample counts, like clock = 32.. it tries to find 32/4 = 8, 32/2 = 16
for (size_t i = pos; i < *size; i++){
if (bits[i] >= high && waveHigh){
smplCnt++;
} else if (bits[i] <= low && !waveHigh){
@ -1434,10 +1446,13 @@ int cleanAskRawDemod(uint8_t *bits, size_t *size, int clk, int invert, int high,
} else { //transition
if ((bits[i] >= high && !waveHigh) || (bits[i] <= low && waveHigh)){
// 32-8-1 = 23
// 32+8+1 = 41
if (smplCnt > clk - cl_4 - 1) { //full clock
if (smplCnt > clk + cl_4 + 1) { //too many samples
errCnt++;
if (g_debugMode == 2) prnt("DEBUG:(cleanAskRawDemod) ASK Modulation Error at: %u", i);
if (g_debugMode == 2) prnt("DEBUG ASK: cleanAskRawDemod ASK Modulation Error FULL at: %u [%u]", i, smplCnt);
bits[bitCnt++] = 7;
} else if (waveHigh) {
bits[bitCnt++] = invert;
@ -1450,7 +1465,16 @@ int cleanAskRawDemod(uint8_t *bits, size_t *size, int clk, int invert, int high,
*startIdx = i - clk;
waveHigh = !waveHigh;
smplCnt = 0;
// 16-8-1 = 7
} else if (smplCnt > cl_2 - cl_4 - 1) { //half clock
if (smplCnt > cl_2 + cl_4 + 1) { //too many samples
errCnt++;
if (g_debugMode == 2) prnt("DEBUG ASK: cleanAskRawDemod ASK Modulation Error HALF at: %u [%u]", i, smplCnt);
bits[bitCnt++] = 7;
}
if (waveHigh) {
bits[bitCnt++] = invert;
} else if (!waveHigh) {