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lfops fcAll: avoid division by zero

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This commit is contained in:
Philippe Teuwen 2019-03-13 00:27:03 +01:00
parent d9308d912d
commit 091ddb26f0
1 changed files with 15 additions and 13 deletions
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28
armsrc/lfops.c
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@ -730,8 +730,6 @@ static void fcAll(uint8_t fc, int *n, uint8_t clock, uint16_t *modCnt) {
uint8_t halfFC = fc >> 1;
uint8_t wavesPerClock = clock / fc;
uint8_t mod = clock % fc; //modifier
uint8_t modAdj = fc / mod; //how often to apply modifier
bool modAdjOk = !(fc % mod); //if (fc % mod==0) modAdjOk = true;
// loop through clock - step field clock
for (uint8_t idx = 0; idx < wavesPerClock; idx++) {
@ -740,19 +738,23 @@ static void fcAll(uint8_t fc, int *n, uint8_t clock, uint16_t *modCnt) {
memset(dest + (*n) + (fc - halfFC), 1, halfFC);
*n += fc;
}
if (mod > 0)(*modCnt)++;
if (mod > 0) {
uint8_t modAdj = fc / mod; //how often to apply modifier
bool modAdjOk = !(fc % mod); //if (fc % mod==0) modAdjOk = true;
(*modCnt)++;
if ((mod > 0) && modAdjOk) { //fsk2
if ((*modCnt % modAdj) == 0) { //if 4th 8 length wave in a rf/50 add extra 8 length wave
memset(dest + (*n), 0, fc - halfFC);
memset(dest + (*n) + (fc - halfFC), 1, halfFC);
*n += fc;
if (modAdjOk) { //fsk2
if ((*modCnt % modAdj) == 0) { //if 4th 8 length wave in a rf/50 add extra 8 length wave
memset(dest + (*n), 0, fc - halfFC);
memset(dest + (*n) + (fc - halfFC), 1, halfFC);
*n += fc;
}
}
if (!modAdjOk) { //fsk1
memset(dest + (*n), 0, mod - (mod >> 1));
memset(dest + (*n) + (mod - (mod >> 1)), 1, mod >> 1);
*n += mod;
}
}
if (mod > 0 && !modAdjOk) { //fsk1
memset(dest + (*n), 0, mod - (mod >> 1));
memset(dest + (*n) + (mod - (mod >> 1)), 1, mod >> 1);
*n += mod;
}
}