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fix: better ASK strong /clipped clock detection.

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This commit is contained in:
iceman1001 2019-03-19 14:41:57 +01:00
parent a41d6fbfb2
commit 54a1d576ee
1 changed files with 44 additions and 4 deletions
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48
common/lfdemod.c
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@ -480,12 +480,25 @@ int DetectStrongAskClock(uint8_t *dest, size_t size, int high, int low, int *clo
size_t startwave;
size_t i = 100;
size_t minClk = 512;
int shortestWaveIdx = 0;
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);
// clock, numoftimes, first idx
uint16_t tmpclk[9][3] = {
{8, 0, 0},
{16, 0, 0},
{32, 0, 0},
{40, 0, 0},
{50, 0, 0},
{64, 0, 0},
{128, 0, 0},
{256, 0, 0},
{384, 0, 0},
};
// loop through all samples (well, we don't want to go out-of-bounds)
while (i < size - 512) {
// measure from low to low
@ -499,11 +512,38 @@ int DetectStrongAskClock(uint8_t *dest, size_t size, int high, int low, int *clo
minClk = i - startwave;
shortestWaveIdx = startwave;
}
int foo = getClosestClock(minClk);
if (foo > 0 ) {
for (uint8_t i = 0; i < 9; i++) {
if ( tmpclk[i][0] == foo ) {
tmpclk[i][1]++;
if ( tmpclk[i][2] == 0) {
tmpclk[i][2] = shortestWaveIdx;
}
break;
}
}
}
}
// set clock
if (g_debugMode == 2) prnt("DEBUG ASK: DetectStrongAskClock smallest wave: %d", minClk);
*clock = getClosestClock(minClk);
// find the clock with most hits and it the first index it was encountered.
int max = 0;
for (uint8_t i = 0; i < 9; i++) {
if (g_debugMode == 2) {
prnt("DEBUG, ASK, clocks %u | hits %u | idx %u"
, tmpclk[i][0]
, tmpclk[i][1]
, tmpclk[i][2]
);
}
if ( max < tmpclk[i][1] ) {
*clock = tmpclk[i][0];
shortestWaveIdx = tmpclk[i][2];
max = tmpclk[i][1];
}
}
if (*clock == 0)
return -1;