FIX: 'lf presco' demod fixes.

[proxmark3-svn] / common / lfdemod.c

diff --git a/common/lfdemod.c b/common/lfdemod.c
index 11340ef003d0b1255e844b3a45cb9d6e6138337d..731496026375c87e1ea69fbb546a0893c03299f9 100644 (file)
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -711,13 +711,12 @@ int Visa2kDemod_AM(uint8_t *dest, size_t *size) {
 
 // find presco preamble 0x10D in already demoded data
 int PrescoDemod(uint8_t *dest, size_t *size) {
-       //make sure buffer has data
-       if (*size < 64*2) return -2;
-
+       if (*size < 128*2) return -1; //make sure buffer has data
        size_t startIdx = 0;
-       uint8_t preamble[] = {1,0,0,0,0,1,1,0,1,0,0,0,0,0,0,0,0,0,0,0};
+       uint8_t preamble[] = {0,0,0,1,0,0,0,0,1,1,0,1,0,0,0,0,0,0,0,0,0,0,0};
        uint8_t errChk = preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx);
-       if (errChk == 0) return -4; //preamble not found
+       if (errChk == 0) return -2; //preamble not found
+       if (*size != 128) return -3; //wrong demoded size
        //return start position
        return (int) startIdx;
 }