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CHG: 'lf search' - hitag/cotag wrong return values

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CHG: is_justnoise - safety checks
CHG: 'hitag reader' - debug printing
This commit is contained in:
iceman1001 2017-10-30 22:20:08 +01:00
commit 3b1c01cd13
6 changed files with 83 additions and 65 deletions
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50
common/lfdemod.c
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@ -143,22 +143,22 @@ bool parityTest(uint32_t bits, uint8_t bitLen, uint8_t pType) {
//by marshmellow
// takes a array of binary values, start position, length of bits per parity (includes parity bit - MAX 32),
// Parity Type (1 for odd; 0 for even; 2 for Always 1's; 3 for Always 0's), and binary Length (length to run)
size_t removeParity(uint8_t *BitStream, size_t startIdx, uint8_t pLen, uint8_t pType, size_t bLen) {
size_t removeParity(uint8_t *bits, size_t startIdx, uint8_t pLen, uint8_t pType, size_t bLen) {
uint32_t parityWd = 0;
size_t bitCnt = 0;
for (int word = 0; word < (bLen); word += pLen){
for (int bit=0; bit < pLen; bit++){
if (word+bit >= bLen) break;
parityWd = (parityWd << 1) | BitStream[startIdx+word+bit];
BitStream[bitCnt++] = (BitStream[startIdx+word+bit]);
parityWd = (parityWd << 1) | bits[startIdx+word+bit];
bits[bitCnt++] = (bits[startIdx+word+bit]);
}
if (word+pLen > bLen) break;
bitCnt--; // overwrite parity with next data
// if parity fails then return 0
switch (pType) {
case 3: if (BitStream[bitCnt]==1) {return 0;} break; //should be 0 spacer bit
case 2: if (BitStream[bitCnt]==0) {return 0;} break; //should be 1 spacer bit
case 3: if (bits[bitCnt]==1) {return 0;} break; //should be 0 spacer bit
case 2: if (bits[bitCnt]==0) {return 0;} break; //should be 1 spacer bit
default: if (parityTest(parityWd, pLen, pType) == 0) { return 0; } break; //test parity
}
parityWd = 0;
@ -196,8 +196,7 @@ size_t addParity(uint8_t *BitSource, uint8_t *dest, uint8_t sourceLen, uint8_t p
return bitCnt;
}
uint32_t bytebits_to_byte(uint8_t *src, size_t numbits)
{
uint32_t bytebits_to_byte(uint8_t *src, size_t numbits) {
uint32_t num = 0;
for(int i = 0 ; i < numbits ; i++) {
num = (num << 1) | (*src);
@ -207,8 +206,7 @@ uint32_t bytebits_to_byte(uint8_t *src, size_t numbits)
}
//least significant bit first
uint32_t bytebits_to_byteLSBF(uint8_t *src, size_t numbits)
{
uint32_t bytebits_to_byteLSBF(uint8_t *src, size_t numbits) {
uint32_t num = 0;
for(int i = 0 ; i < numbits ; i++) {
num = (num << 1) | *(src + (numbits-(i+1)));
@ -225,14 +223,14 @@ bool preambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *
// search for given preamble in given BitStream and return success=1 or fail=0 and startIndex (where it was found) and length if not fineone
// fineone does not look for a repeating preamble for em4x05/4x69 sends preamble once, so look for it once in the first pLen bits
//(iceman) FINDONE, only finds start index. NOT SIZE!. I see Em410xDecode (lfdemod.c) uses SIZE to determine success
bool preambleSearchEx(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx, bool findone)
bool preambleSearchEx(uint8_t *bits, uint8_t *preamble, size_t pLen, size_t *size, size_t *startIdx, bool findone)
{
// Sanity check. If preamble length is bigger than bitstream length.
// Sanity check. If preamble length is bigger than bits length.
if ( *size <= pLen ) return false;
uint8_t foundCnt = 0;
for (size_t idx = 0; idx < *size - pLen; idx++) {
if (memcmp(BitStream+idx, preamble, pLen) == 0){
if (memcmp(bits+idx, preamble, pLen) == 0){
//first index found
foundCnt++;
if (foundCnt == 1){
@ -590,7 +588,7 @@ int DetectStrongNRZClk(uint8_t *dest, size_t size, int peak, int low, bool *stro
++i;
lastWasHigh = (dest[i] >= peak);
if (i==size) return 0;
if (i == size) return 0;
transition1 = i;
for (;i < size; i++) {
@ -1257,19 +1255,19 @@ int BiphaseRawDecode(uint8_t *bits, size_t *size, int *offset, int invert) {
//by marshmellow
//take 10 and 01 and manchester decode
//run through 2 times and take least errCnt
int manrawdecode(uint8_t *BitStream, size_t *size, uint8_t invert, uint8_t *alignPos){
int manrawdecode(uint8_t *bits, size_t *size, uint8_t invert, uint8_t *alignPos){
// sanity check
if (*size < 16) return -1;
int errCnt = 0, bestErr = 1000;
uint16_t bitnum = 0, MaxBits = 512, bestRun = 0;
uint16_t bitnum = 0, maxBits = 512, bestRun = 0;
size_t i, k;
//find correct start position [alignment]
for (k = 0; k < 2; ++k){
for (i = k; i < *size-3; i += 2) {
if (BitStream[i] == BitStream[i+1])
if (bits[i] == bits[i+1])
errCnt++;
}
if (bestErr > errCnt){
@ -1281,14 +1279,14 @@ int manrawdecode(uint8_t *BitStream, size_t *size, uint8_t invert, uint8_t *alig
*alignPos = bestRun;
//decode
for (i = bestRun; i < *size-3; i += 2){
if (BitStream[i] == 1 && (BitStream[i+1] == 0)){
BitStream[bitnum++] = invert;
} else if ((BitStream[i] == 0) && BitStream[i+1] == 1){
BitStream[bitnum++] = invert^1;
if (bits[i] == 1 && (bits[i+1] == 0)){
bits[bitnum++] = invert;
} else if ((bits[i] == 0) && bits[i+1] == 1){
bits[bitnum++] = invert^1;
} else {
BitStream[bitnum++] = 7;
bits[bitnum++] = 7;
}
if (bitnum > MaxBits) break;
if (bitnum > maxBits) break;
}
*size = bitnum;
return bestErr;
@ -1440,11 +1438,15 @@ int askdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr
// peaks invert bit (high=1 low=0) each clock cycle = 1 bit determined by last peak
int nrzRawDemod(uint8_t *dest, size_t *size, int *clk, int *invert, int *startIdx) {
if (justNoise(dest, *size)) return -1;
size_t clkStartIdx = 0;
*clk = DetectNRZClock(dest, *size, *clk, &clkStartIdx);
if (*clk==0) return -2;
if (*clk == 0) return -2;
size_t i, gLen = 4096;
if (gLen>*size) gLen = *size-20;
if (gLen > *size)
gLen = *size-20;
int high, low;
if (getHiLo(dest, gLen, &high, &low, 75, 75) < 1) return -3; //25% fuzz on high 25% fuzz on low