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moved function

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This commit is contained in:
iceman1001 2017-12-23 11:23:14 +01:00
parent 18a828d2fd
commit 74b4755d42
2 changed files with 42 additions and 4 deletions
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45
common/lfdemod.c
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@ -232,6 +232,16 @@ size_t addParity(uint8_t *src, uint8_t *dest, uint8_t sourceLen, uint8_t pLen, u
return bitCnt;
}
// array must be size dividable with 8
uint8_t bits_to_array(const uint8_t *bits, size_t size, uint8_t *dest) {
if ( (size == 0) || (size % 8) != 0) return 0;
for(uint32_t i = 0; i < (size / 8); i++)
dest[i] = bytebits_to_byte((uint8_t *) bits + (i * 8), 8);
return 0;
}
uint32_t bytebits_to_byte(uint8_t *src, size_t numbits) {
uint32_t num = 0;
for(int i = 0 ; i < numbits ; i++) {
@ -1553,10 +1563,37 @@ size_t fsk_wave_demod(uint8_t *dest, size_t size, uint8_t fchigh, uint8_t fclow,
last_transition = idx;
idx++;
size_t numBits = 0;
// count cycles between consecutive lo-hi transitions, there should be either 8 (fc/8)
// or 10 (fc/10) cycles but in practice due to noise etc we may end up with anywhere
// between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10
// (could also be fc/5 && fc/7 for fsk1 = 4-9)
// Definition: cycles between consecutive lo-hi transitions
// Lets define some expected lengths. FSK1 is easier since it has bigger differences between.
// FSK1 8/5
// 50/8 = 6 | 40/8 = 5 | 64/8 = 8
// 50/5 = 10 | 40/5 = 8 | 64/5 = 12
// FSK2 10/8
// 50/10 = 5 | 40/10 = 4 | 64/10 = 6
// 50/8 = 6 | 40/8 = 5 | 64/8 = 8
// count cycles between consecutive lo-hi transitions,
// in practice due to noise etc we may end up with anywhere
// To allow fuzz would mean +-1 on expected cycle width.
// FSK1 8/5
// 50/8 = 6 (5-7) | 40/8 = 5 (4-6) | 64/8 = 8 (7-9)
// 50/5 = 10 (9-11) | 40/5 = 8 (7-9) | 64/5 = 12 (11-13)
// FSK2 10/8
// 50/10 = 5 (4-6) | 40/10 = 4 (3-5) | 64/10 = 6 (5-7)
// 50/8 = 6 (5-7) | 40/8 = 5 (4-6) | 64/8 = 8 (7-9)
//
// It easy to see to the overgaping, but luckily we the group value also, like 1111000001111
// to separate between which bit to demodulate to.
// process:
// count width from 0-1 transition to 1-0.
// determine the width is withing FUZZ_min and FUZZ_max tolerances
// width should be divided with exp_one. i:e 6+7+6+2=21, 21/5 = 4,
// the 1-0 to 0-1 width should be divided with exp_zero. Ie: 3+5+6+7 = 21/6 = 3
for(; idx < size-20; idx++) {
// threshold current value
if (dest[idx] < FSK_PSK_THRESHOLD) dest[idx] = 0;

1
common/lfdemod.h
View file

@ -46,6 +46,7 @@ extern int askdemod(uint8_t *bits, size_t *size, int *clk, int *invert, int
extern int askdemod_ext(uint8_t *bits, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp, uint8_t askType, int *startIdx);
extern void askAmp(uint8_t *bits, size_t size);
extern int BiphaseRawDecode(uint8_t *bits, size_t *size, int *offset, int invert);
extern uint8_t bits_to_array(const uint8_t *bits, size_t size, uint8_t *dest);
extern uint32_t bytebits_to_byte(uint8_t *src, size_t numbits);
extern uint32_t bytebits_to_byteLSBF(uint8_t *src, size_t numbits);
extern uint16_t countFC(uint8_t *bits, size_t size, uint8_t fskAdj);