From dc065b4e3467effd6b4f695dd3bc781da872d394 Mon Sep 17 00:00:00 2001 From: marshmellow42 Date: Tue, 13 Jan 2015 17:52:48 -0500 Subject: [PATCH 1/1] slight em410xdecode adjustments a little faster --- common/lfdemod.c | 20 ++++---------------- 1 file changed, 4 insertions(+), 16 deletions(-) diff --git a/common/lfdemod.c b/common/lfdemod.c index 2352caad..062818ef 100644 --- a/common/lfdemod.c +++ b/common/lfdemod.c @@ -19,21 +19,9 @@ uint64_t Em410xDecode(uint8_t *BitStream, size_t size) //no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future // otherwise could be a void with no arguments //set defaults - int high=0, low=255; uint64_t lo=0; - uint32_t i = 0; - uint32_t initLoopMax = 65; - if (initLoopMax>size) initLoopMax=size; - - for (;i < initLoopMax; ++i) //65 samples should be plenty to find high and low values - { - if (BitStream[i] > high) - high = BitStream[i]; - else if (BitStream[i] < low) - low = BitStream[i]; - } - if (((high !=1)||(low !=0))){ //allow only 1s and 0s + if (BitStream[10]>1){ //allow only 1s and 0s // PrintAndLog("no data found"); return 0; } @@ -51,9 +39,9 @@ uint64_t Em410xDecode(uint8_t *BitStream, size_t size) idx+=9; for (i=0; i<10;i++){ for(ii=0; ii<5; ++ii){ - parityTest += BitStream[(i*5)+ii+idx]; + parityTest ^= BitStream[(i*5)+ii+idx]; } - if (parityTest== ((parityTest>>1)<<1)){ + if (!parityTest){ parityTest=0; for (ii=0; ii<4;++ii){ lo=(lo<<1LL)|(BitStream[(i*5)+ii+idx]); @@ -63,7 +51,7 @@ uint64_t Em410xDecode(uint8_t *BitStream, size_t size) //PrintAndLog("DEBUG: EM parity failed parity val: %d, i:%d, ii:%d,idx:%d, Buffer: %d%d%d%d%d",parityTest,i,ii,idx,BitStream[idx+ii+(i*5)-5],BitStream[idx+ii+(i*5)-4],BitStream[idx+ii+(i*5)-3],BitStream[idx+ii+(i*5)-2],BitStream[idx+ii+(i*5)-1]); parityTest=0; idx-=8; - if (resetCnt>5)return 0; + if (resetCnt>5)return 0; //try 5 times resetCnt++; goto restart;//continue; } -- 2.39.5