ADD: marshmellows new lf command and DetectClock. (works great!)

[proxmark3-svn] / client / graph.c

diff --git a/client/graph.c b/client/graph.c
index 7b45f3f2f1cf00d1df8bf1295fdb04d0dafd79b2..bb8159951b2eb8c4637b5a0664f3fbb33d690ed3 100644 (file)
--- a/client/graph.c
+++ b/client/graph.c
@@ -51,13 +51,15 @@ int ClearGraph(int redraw)
 /*
  * Detect clock rate
  */
-int DetectClock(int peak)
+ //decommissioned - has difficulty detecting rf/32 and only works if data is manchester encoded
+/*
+int DetectClock2(int peak)
 {
   int i;
   int clock = 0xFFFF;
   int lastpeak = 0;
 
-  /* Detect peak if we don't have one */
+  // Detect peak if we don't have one 
   if (!peak)
     for (i = 0; i < GraphTraceLen; ++i)
       if (GraphBuffer[i] > peak)
@@ -65,36 +67,90 @@ int DetectClock(int peak)
 
   for (i = 1; i < GraphTraceLen; ++i)
   {
-    /* If this is the beginning of a peak */
-    if (GraphBuffer[i - 1] != GraphBuffer[i] && GraphBuffer[i] == peak)
+    // If this is the beginning of a peak 
+    if (GraphBuffer[i - 1] != GraphBuffer[i] && GraphBuffer[i] >= peak)
     {
-      /* Find lowest difference between peaks */
+      // Find lowest difference between peaks 
       if (lastpeak && i - lastpeak < clock)
         clock = i - lastpeak;
       lastpeak = i;
     }
   }
        
-       int clockmod = clock%8;
-       if ( clockmod == 0) 
                return clock;
-       
-       // When detected clock is 31 or 33 then return 32
+}
+*/
 
-       printf("Found clock at %d ", clock);
-       switch( clockmod )
+// by marshmellow
+// not perfect especially with lower clocks or VERY good antennas (heavy wave clipping)
+// maybe somehow adjust peak trimming value based on samples to fix?
+int DetectClock(int peak)
        {
-               case 7: clock++; break;
-               case 6: clock += 2 ; break;
-               case 1: clock--; break;
-               case 2: clock -= 2; break;
-       }
-       if ( clock < 32) 
-               clock = 32;
-               
-       printf("- adjusted it to %d \n", clock);
-       return clock;
+  int i=0;
+  int low=0;
+  int clk[]={16,32,40,50,64,100,128,256};
+  if (!peak){
+    for (i=0;i<GraphTraceLen;++i){
+      if(GraphBuffer[i]>peak){
+        peak = GraphBuffer[i]; 
+      }
+      if(GraphBuffer[i]<low){
+        low = GraphBuffer[i];
+      }
+    }
+    peak=(int)(peak*.75);
+    low= (int)(low*.75);
+  }
+  //int numbits;
+  int ii;
+  int loopCnt = 256;
+  if (GraphTraceLen<loopCnt) loopCnt = GraphTraceLen;
+  int clkCnt;
+  int tol = 0;
+  int bestErr=1000;
+  int errCnt[]={0,0,0,0,0,0,0,0};
+ // int good;
+  for(clkCnt=0; clkCnt<6;++clkCnt){
+    if (clk[clkCnt]==32){
+      tol=1;
+    }else{
+      tol=0;
+    }
+    bestErr=1000;
+    for (ii=0; ii<loopCnt; ++ii){
+      if ((GraphBuffer[ii]>=peak) || (GraphBuffer[ii]<=low)){
+        //numbits=0;
+        //good=1;
+        errCnt[clkCnt]=0;
+        for (i=0; i<((int)(GraphTraceLen/clk[clkCnt])-1); ++i){
+          if (GraphBuffer[ii+(i*clk[clkCnt])]>=peak || GraphBuffer[ii+(i*clk[clkCnt])]<=low){
+            //numbits++;
+          }else if(GraphBuffer[ii+(i*clk[clkCnt])-tol]>=peak || GraphBuffer[ii+(i*clk[clkCnt])-tol]<=low){
+          }else if(GraphBuffer[ii+(i*clk[clkCnt])+tol]>=peak || GraphBuffer[ii+(i*clk[clkCnt])+tol]<=low){
+          }else{  //error no peak detected
+            //numbits=0;
+            //good=0;
+            errCnt[clkCnt]++;
+            //break;
+          }    
+        }
+        if(errCnt[clkCnt]==0) return clk[clkCnt];
+        if(errCnt[clkCnt]<bestErr) bestErr=errCnt[clkCnt];
+      }
+    } 
+    errCnt[clkCnt]=bestErr;
+  }
+  int iii=0;
+  int best=0;
+  for (iii=0; iii<6;++iii){
+    if (errCnt[iii]<errCnt[best]){
+      best = iii;
+    }
+  }
+  PrintAndLog("clkCnt: %d, ii: %d, i: %d peak: %d, low: %d, errcnt: %d, errCnt64: %d",clkCnt,ii,i,peak,low,errCnt[best],errCnt[4]);
+  return clk[best];
 }
+               
 
 /* Get or auto-detect clock rate */
 int GetClock(const char *str, int peak, int verbose)
@@ -109,6 +165,7 @@ int GetClock(const char *str, int peak, int verbose)
   if (!clock)
   {
     clock = DetectClock(peak);
+    //clock2 = DetectClock2(peak);
     /* Only print this message if we're not looping something */
     if (!verbose)
       PrintAndLog("Auto-detected clock rate: %d", clock);