Some documentation and formatting to LogTraceHitag

diff --git a/armsrc/BigBuf.c b/armsrc/BigBuf.c
index 18db66f3b2d3e0d90505c95ab40d4c728b65efa6..6e99a793fe72194db6be454eb689d655a02ec2e6 100644 (file)
--- a/armsrc/BigBuf.c
+++ b/armsrc/BigBuf.c
@@ -185,27 +185,38 @@ bool RAMFUNC LogTrace(const uint8_t *btBytes, uint16_t iLen, uint32_t timestamp_
 }
 int LogTraceHitag(const uint8_t * btBytes, int iBits, int iSamples, uint32_t dwParity, int bReader)
 {
-       static uint16_t traceLen = 0;
-       uint8_t *trace = BigBuf_get_addr();
 
+       if (!tracing) return FALSE;
+
+       uint8_t *trace = BigBuf_get_addr();
+       uint16_t iLen = nbytes(iBits);
        // Return when trace is full
-       if (traceLen + sizeof(rsamples) + sizeof(dwParity) + sizeof(iBits) + nbytes(iBits) > BigBuf_max_traceLen()) return FALSE;
+       if (traceLen + sizeof(rsamples) + sizeof(dwParity) + sizeof(iBits) + iLen > BigBuf_max_traceLen()) return FALSE;
+
+       //Hitag traces appear to use this traceformat:
+       // 32 bits timestamp (little endian,Highest Bit used as readerToTag flag)
+       // 32 bits parity
+       // 8 bits size (number of bits in the trace entry)
+       // y Bytes data
 
-       // Trace the random, i'm curious
        rsamples += iSamples;
        trace[traceLen++] = ((rsamples >> 0) & 0xff);
        trace[traceLen++] = ((rsamples >> 8) & 0xff);
        trace[traceLen++] = ((rsamples >> 16) & 0xff);
        trace[traceLen++] = ((rsamples >> 24) & 0xff);
+
        if (!bReader) {
-       trace[traceLen - 1] |= 0x80;
+               trace[traceLen - 1] |= 0x80;
        }
+
        trace[traceLen++] = ((dwParity >> 0) & 0xff);
        trace[traceLen++] = ((dwParity >> 8) & 0xff);
        trace[traceLen++] = ((dwParity >> 16) & 0xff);
        trace[traceLen++] = ((dwParity >> 24) & 0xff);
        trace[traceLen++] = iBits;
-       memcpy(trace + traceLen, btBytes, nbytes(iBits));
-       traceLen += nbytes(iBits);
+
+       memcpy(trace + traceLen, btBytes, iLen);
+       traceLen += iLen;
+
        return TRUE;
 }

diff --git a/armsrc/util.c b/armsrc/util.c
index 889319279750290a9d3627cc177b49eb4e9025bf..74fba94b764db748cf6a377ba23b96f5d06bc304 100644 (file)
--- a/armsrc/util.c
+++ b/armsrc/util.c
@@ -35,7 +35,7 @@ void print_result(char *name, uint8_t *buf, size_t len) {
 }
 
 size_t nbytes(size_t nbits) {
-       return (nbits/8)+((nbits%8)>0);
+       return (nbits >> 3)+((nbits % 8) > 0);
 }
 
 uint32_t SwapBits(uint32_t value, int nrbits) {