lf updates

[proxmark3-svn] / common / lfdemod.c

diff --git a/common/lfdemod.c b/common/lfdemod.c
index 5b0bc29d28dfb61fd8daf75e07ceb64603c930be..c7acb404bac93319c4176eafb494654200a96cf6 100644 (file)
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -375,34 +375,39 @@ int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int
                        smplCnt++;
                } else if (BinStream[i] <= low && !waveHigh){
                        smplCnt++;
-               } else { //not high or low or a transition
-                       if (smplCnt > clk-(clk/4)) { //full clock
-                               if (smplCnt > clk + (clk/4)) { //too many samples
-                                       errCnt++;
-                                       BinStream[bitCnt++]=77;
-                               } else if (waveHigh) {
-                                       BinStream[bitCnt++] = invert;
-                                       BinStream[bitCnt++] = invert;
-                               } else if (!waveHigh) {
-                                       BinStream[bitCnt++] = invert ^ 1;
-                                       BinStream[bitCnt++] = invert ^ 1;
-                               }
-                               waveHigh ^= 1;  
-                               smplCnt = 0;
-                       } else if (smplCnt > (clk/2) - (clk/5)) {
-                               if (waveHigh) {
-                                       BinStream[bitCnt++] = invert;
-                               } else if (!waveHigh) {
-                                       BinStream[bitCnt++] = invert ^ 1;
+               } else { //transition
+                       if ((BinStream[i] >= high && !waveHigh) || (BinStream[i] <= low && waveHigh)){
+                               if (smplCnt > clk-(clk/4)-1) { //full clock
+                                       if (smplCnt > clk + (clk/4)+1) { //too many samples
+                                               errCnt++;
+                                               BinStream[bitCnt++]=77;
+                                       } else if (waveHigh) {
+                                               BinStream[bitCnt++] = invert;
+                                               BinStream[bitCnt++] = invert;
+                                       } else if (!waveHigh) {
+                                               BinStream[bitCnt++] = invert ^ 1;
+                                               BinStream[bitCnt++] = invert ^ 1;
+                                       }
+                                       waveHigh ^= 1;  
+                                       smplCnt = 0;
+                               } else if (smplCnt > (clk/2) - (clk/4)-1) {
+                                       if (waveHigh) {
+                                               BinStream[bitCnt++] = invert;
+                                       } else if (!waveHigh) {
+                                               BinStream[bitCnt++] = invert ^ 1;
+                                       }
+                                       waveHigh ^= 1;  
+                                       smplCnt = 0;
+                               } else if (!bitCnt) {
+                                       //first bit
+                                       waveHigh = (BinStream[i] >= high);
+                                       smplCnt = 1;
+                               } else {
+                                       smplCnt++;
+                                       //transition bit oops
                                }
-                               waveHigh ^= 1;  
-                               smplCnt = 0;
-                       } else if (!bitCnt) {
-                               //first bit
-                               waveHigh = (BinStream[i] >= high);
-                               smplCnt = 1;
-                       } else {
-                               //transition bit? ignore
+                       } else { //haven't hit new high or new low yet
+                               smplCnt++;
                        }
                }
        }
@@ -888,16 +893,18 @@ int PyramiddemodFSK(uint8_t *dest, size_t *size)
 
 uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low)
 {
-       uint8_t allPeaks=1;
+       uint16_t allPeaks=1;
        uint16_t cntPeaks=0;
-       for (size_t i=30; i<255; i++){
+       size_t loopEnd = 572;
+       if (loopEnd > size) loopEnd = size;
+       for (size_t i=60; i<loopEnd; i++){
                if (dest[i]>low && dest[i]<high) 
                        allPeaks=0;
                else
                        cntPeaks++;
        }
-       if (allPeaks==0){
-               if (cntPeaks>210) return 1;
+       if (allPeaks == 0){
+               if (cntPeaks > 300) return 1;
        }
        return allPeaks;
 }
@@ -939,10 +946,12 @@ int DetectStrongAskClock(uint8_t dest[], size_t size)
                        }
                }
        }
+       uint8_t tol;
        for (idx=8; idx>0; idx--){
-               if (clk[idx] >= highCnt && clk[idx] <= highCnt+2)
+               tol = clk[idx]/8;
+               if (clk[idx] >= highCnt - tol && clk[idx] <= highCnt + tol)
                        return clk[idx];
-               if (clk[idx] >= highCnt2 && clk[idx] <= highCnt2+2)
+               if (clk[idx] >= highCnt2 - tol && clk[idx] <= highCnt2 + tol)
                        return clk[idx];
        }
        return -1;