adjust lf search to not use save/restore if...

[proxmark3-svn] / common / lfdemod.c

diff --git a/common/lfdemod.c b/common/lfdemod.c
index d6ef88a40280e57d3e241baffc772bfd70e1aeed..d2e0fca42b4cab88ae4995575a482a5afe3ca021 100644 (file)
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -1130,10 +1130,10 @@ int millerRawDecode(uint8_t *BitStream, size_t *size, int invert) {
 //take 01 or 10 = 1 and 11 or 00 = 0
 //check for phase errors - should never have 111 or 000 should be 01001011 or 10110100 for 1010
 //decodes biphase or if inverted it is AKA conditional dephase encoding AKA differential manchester encoding
-int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert) {
+int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int *offset, int invert) {
        uint16_t bitnum = 0;
        uint16_t errCnt = 0;
-       size_t i = offset;
+       size_t i = *offset;
        uint16_t MaxBits=512;
        //if not enough samples - error
        if (*size < 51) return -1;
@@ -1143,8 +1143,8 @@ int BiphaseRawDecode(uint8_t *BitStream, size_t *size, int offset, int invert) {
                if (BitStream[i+1]==BitStream[i+2]) offsetA=0; 
                if (BitStream[i+2]==BitStream[i+3]) offsetB=0;                                  
        }
-       if (!offsetA && offsetB) offset++;
-       for (i=offset; i<*size-3; i+=2){
+       if (!offsetA && offsetB) *offset+=1;
+       for (i=*offset; i<*size-3; i+=2){
                //check for phase error
                if (BitStream[i+1]==BitStream[i+2]) {
                        BitStream[bitnum++]=7;
@@ -1489,18 +1489,14 @@ size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert,
 
 //by marshmellow  (from holiman's base)
 // full fsk demod from GraphBuffer wave to decoded 1s and 0s (no mandemod)
-int fskdemod_ext(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t fchigh, uint8_t fclow, int *startIdx) {
+int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t fchigh, uint8_t fclow, int *startIdx) {
+       if (justNoise(dest, size)) return 0;
        // FSK demodulator
        size = fsk_wave_demod(dest, size, fchigh, fclow, startIdx);
        size = aggregate_bits(dest, size, rfLen, invert, fchigh, fclow, startIdx);
        return size;
 }
 
-int fskdemod(uint8_t *dest, size_t size, uint8_t rfLen, uint8_t invert, uint8_t fchigh, uint8_t fclow) {
-       int startIdx=0;
-       return fskdemod_ext(dest, size, rfLen, invert, fchigh, fclow, &startIdx);
-}
-
 // by marshmellow
 // convert psk1 demod to psk2 demod
 // only transition waves are 1s
@@ -1627,14 +1623,12 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert) {
 
 // by marshmellow
 // FSK Demod then try to locate an AWID ID
-int AWIDdemodFSK(uint8_t *dest, size_t *size) {
+int AWIDdemodFSK(uint8_t *dest, size_t *size, int *waveStartIdx) {
        //make sure buffer has enough data
        if (*size < 96*50) return -1;
 
-       if (justNoise(dest, *size)) return -2;
-
        // FSK demodulator
-       *size = fskdemod(dest, *size, 50, 1, 10, 8);  // fsk2a RF/50 
+       *size = fskdemod(dest, *size, 50, 1, 10, 8, waveStartIdx);  // fsk2a RF/50 
        if (*size < 96) return -3;  //did we get a good demod?
 
        uint8_t preamble[] = {0,0,0,0,0,0,0,1};
@@ -1716,12 +1710,10 @@ int gProxII_Demod(uint8_t BitStream[], size_t *size) {
 }
 
 // loop to get raw HID waveform then FSK demodulate the TAG ID from it
-int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) {
-       if (justNoise(dest, *size)) return -1;
-
+int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo, int *waveStartIdx) {
        size_t numStart=0, size2=*size, startIdx=0; 
-       // FSK demodulator
-       *size = fskdemod(dest, size2,50,1,10,8); //fsk2a
+       // FSK demodulator  fsk2a so invert and fc/10/8
+       *size = fskdemod(dest, size2, 50, 1, 10, 8, waveStartIdx);
        if (*size < 96*2) return -2;
        // 00011101 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1
        uint8_t preamble[] = {0,0,0,1,1,1,0,1};
@@ -1746,12 +1738,11 @@ int HIDdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32
        return (int)startIdx;
 }
 
-int IOdemodFSK(uint8_t *dest, size_t size) {
-       if (justNoise(dest, size)) return -1;
+int IOdemodFSK(uint8_t *dest, size_t size, int *waveStartIdx) {
        //make sure buffer has data
        if (size < 66*64) return -2;
-       // FSK demodulator
-       size = fskdemod(dest, size, 64, 1, 10, 8);  // FSK2a RF/64 
+       // FSK demodulator  RF/64, fsk2a so invert, and fc/10/8
+       size = fskdemod(dest, size, 64, 1, 10, 8, waveStartIdx); 
        if (size < 65) return -3;  //did we get a good demod?
        //Index map
        //0           10          20          30          40          50          60
@@ -1796,12 +1787,10 @@ int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert) {
 }
 
 // loop to get raw paradox waveform then FSK demodulate the TAG ID from it
-int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo) {
-       if (justNoise(dest, *size)) return -1;
-       
+int ParadoxdemodFSK(uint8_t *dest, size_t *size, uint32_t *hi2, uint32_t *hi, uint32_t *lo, int *waveStartIdx) {
        size_t numStart=0, size2=*size, startIdx=0;
        // FSK demodulator
-       *size = fskdemod(dest, size2,50,1,10,8); //fsk2a
+       *size = fskdemod(dest, size2,50,1,10,8,waveStartIdx); //fsk2a
        if (*size < 96) return -2;
 
        // 00001111 bit pattern represent start of frame, 01 pattern represents a 0 and 10 represents a 1
@@ -1841,15 +1830,12 @@ int PrescoDemod(uint8_t *dest, size_t *size) {
 
 // by marshmellow
 // FSK Demod then try to locate a Farpointe Data (pyramid) ID
-int PyramiddemodFSK(uint8_t *dest, size_t *size) {
+int PyramiddemodFSK(uint8_t *dest, size_t *size, int *waveStartIdx) {
        //make sure buffer has data
        if (*size < 128*50) return -5;
 
-       //test samples are not just noise
-       if (justNoise(dest, *size)) return -1;
-
        // FSK demodulator
-       *size = fskdemod(dest, *size, 50, 1, 10, 8);  // fsk2a RF/50 
+       *size = fskdemod(dest, *size, 50, 1, 10, 8, waveStartIdx);  // fsk2a RF/50 
        if (*size < 128) return -2;  //did we get a good demod?
 
        uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1};