X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/40148ab609cdcf58ae6ef517c319a758006e1c6d..11081e0459f303518350b195b9d1c54b415eb6d7:/common/lfdemod.c?ds=inline

diff --git a/common/lfdemod.c b/common/lfdemod.c
index 96b187b7..144cb327 100644
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -25,7 +25,7 @@ uint8_t justNoise(uint8_t *BitStream, size_t size)
 }
 
 //by marshmellow
-//get high and low with passed in fuzz factor. also return noise test = 1 for passed or 0 for only noise
+//get high and low values of a wave with passed in fuzz factor. also return noise test = 1 for passed or 0 for only noise
 int getHiLo(uint8_t *BitStream, size_t size, int *high, int *low, uint8_t fuzzHi, uint8_t fuzzLo)
 {
 	*high=0;
@@ -354,7 +354,6 @@ void askAmp(uint8_t *BitStream, size_t size)
 //by marshmellow
 //takes 3 arguments - clock, invert and maxErr as integers
 //attempts to demodulate ask only
-//prints binary found and saves in graphbuffer for further commands
 int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr, uint8_t amp)
 {
 	uint32_t i;
@@ -501,6 +500,28 @@ int askrawdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int max
 	}
 	return bestErrCnt;
 }
+
+// demod gProxIIDemod 
+// error returns as -x 
+// success returns start position in BitStream
+// BitStream must contain previously askrawdemod and biphasedemoded data
+int gProxII_Demod(uint8_t BitStream[], size_t *size)
+{
+	size_t startIdx=0;
+	uint8_t preamble[] = {1,1,1,1,1,0};
+
+	uint8_t errChk = preambleSearch(BitStream, preamble, sizeof(preamble), size, &startIdx);
+	if (errChk == 0) return -3; //preamble not found
+	if (*size != 96) return -2; //should have found 96 bits
+	//check first 6 spacer bits to verify format
+	if (!BitStream[startIdx+5] && !BitStream[startIdx+10] && !BitStream[startIdx+15] && !BitStream[startIdx+20] && !BitStream[startIdx+25] && !BitStream[startIdx+30]){
+		//confirmed proper separator bits found
+		//return start position
+		return (int) startIdx;
+	}
+	return -5;
+}
+
 //translate wave to 11111100000 (1 for each short wave 0 for each long wave)
 size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow)
 {
@@ -1068,6 +1089,23 @@ void psk1TOpsk2(uint8_t *BitStream, size_t size)
 	return;
 }
 
+// by marshmellow
+// convert psk2 demod to psk1 demod
+// from only transition waves are 1s to phase shifts change bit
+void psk2TOpsk1(uint8_t *BitStream, size_t size)
+{
+	size_t i;
+	uint8_t phase=BitStream[0];
+	//uint8_t lastBit=BitStream[0];
+	for (i=1; i<size; i++){
+		if (phase!=BitStream[i]){
+			phase ^=1;
+		}
+		BitStream[i]=phase;
+	}
+	return;
+}
+
 // redesigned by marshmellow adjusted from existing decode functions
 // indala id decoding - only tested on 26 bit tags, but attempted to make it work for more
 int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert)