+int CmdFSKdemod(const char *Cmd) //old CmdFSKdemod needs updating
+{
+ static const int LowTone[] = {
+ 1, 1, 1, 1, 1, -1, -1, -1, -1, -1,
+ 1, 1, 1, 1, 1, -1, -1, -1, -1, -1,
+ 1, 1, 1, 1, 1, -1, -1, -1, -1, -1,
+ 1, 1, 1, 1, 1, -1, -1, -1, -1, -1,
+ 1, 1, 1, 1, 1, -1, -1, -1, -1, -1
+ };
+ static const int HighTone[] = {
+ 1, 1, 1, 1, 1, -1, -1, -1, -1,
+ 1, 1, 1, 1, -1, -1, -1, -1,
+ 1, 1, 1, 1, -1, -1, -1, -1,
+ 1, 1, 1, 1, -1, -1, -1, -1,
+ 1, 1, 1, 1, -1, -1, -1, -1,
+ 1, 1, 1, 1, -1, -1, -1, -1, -1,
+ };
+
+ int lowLen = sizeof (LowTone) / sizeof (int);
+ int highLen = sizeof (HighTone) / sizeof (int);
+ int convLen = (highLen > lowLen) ? highLen : lowLen;
+ uint32_t hi = 0, lo = 0;
+
+ int i, j;
+ int minMark = 0, maxMark = 0;
+
+ for (i = 0; i < GraphTraceLen - convLen; ++i) {
+ int lowSum = 0, highSum = 0;
+
+ for (j = 0; j < lowLen; ++j) {
+ lowSum += LowTone[j]*GraphBuffer[i+j];
+ }
+ for (j = 0; j < highLen; ++j) {
+ highSum += HighTone[j] * GraphBuffer[i + j];
+ }
+ lowSum = abs(100 * lowSum / lowLen);
+ highSum = abs(100 * highSum / highLen);
+ GraphBuffer[i] = (highSum << 16) | lowSum;
+ }
+
+ for(i = 0; i < GraphTraceLen - convLen - 16; ++i) {
+ int lowTot = 0, highTot = 0;
+ // 10 and 8 are f_s divided by f_l and f_h, rounded
+ for (j = 0; j < 10; ++j) {
+ lowTot += (GraphBuffer[i+j] & 0xffff);
+ }
+ for (j = 0; j < 8; j++) {
+ highTot += (GraphBuffer[i + j] >> 16);
+ }
+ GraphBuffer[i] = lowTot - highTot;
+ if (GraphBuffer[i] > maxMark) maxMark = GraphBuffer[i];
+ if (GraphBuffer[i] < minMark) minMark = GraphBuffer[i];
+ }
+
+ GraphTraceLen -= (convLen + 16);
+ RepaintGraphWindow();
+
+ // Find bit-sync (3 lo followed by 3 high) (HID ONLY)
+ int max = 0, maxPos = 0;
+ for (i = 0; i < 6000; ++i) {
+ int dec = 0;
+ for (j = 0; j < 3 * lowLen; ++j) {
+ dec -= GraphBuffer[i + j];
+ }
+ for (; j < 3 * (lowLen + highLen ); ++j) {
+ dec += GraphBuffer[i + j];
+ }
+ if (dec > max) {
+ max = dec;
+ maxPos = i;
+ }
+ }
+
+ // place start of bit sync marker in graph
+ GraphBuffer[maxPos] = maxMark;
+ GraphBuffer[maxPos + 1] = minMark;
+
+ maxPos += j;
+
+ // place end of bit sync marker in graph
+ GraphBuffer[maxPos] = maxMark;
+ GraphBuffer[maxPos+1] = minMark;
+
+ PrintAndLog("actual data bits start at sample %d", maxPos);
+ PrintAndLog("length %d/%d", highLen, lowLen);
+
+ uint8_t bits[46] = {0x00};
+
+ // find bit pairs and manchester decode them
+ for (i = 0; i < arraylen(bits) - 1; ++i) {
+ int dec = 0;
+ for (j = 0; j < lowLen; ++j) {
+ dec -= GraphBuffer[maxPos + j];
+ }
+ for (; j < lowLen + highLen; ++j) {
+ dec += GraphBuffer[maxPos + j];
+ }
+ maxPos += j;
+ // place inter bit marker in graph
+ GraphBuffer[maxPos] = maxMark;
+ GraphBuffer[maxPos + 1] = minMark;
+
+ // hi and lo form a 64 bit pair
+ hi = (hi << 1) | (lo >> 31);
+ lo = (lo << 1);
+ // store decoded bit as binary (in hi/lo) and text (in bits[])
+ if(dec < 0) {
+ bits[i] = '1';
+ lo |= 1;
+ } else {
+ bits[i] = '0';
+ }
+ }
+ PrintAndLog("bits: '%s'", bits);
+ PrintAndLog("hex: %08x %08x", hi, lo);
+ return 0;
+}