]> git.zerfleddert.de Git - proxmark3-svn/commitdiff
simplify some code, add comments
authormarshmellow42 <marshmellowrf@gmail.com>
Sat, 19 Mar 2016 04:09:58 +0000 (00:09 -0400)
committermarshmellow42 <marshmellowrf@gmail.com>
Sat, 19 Mar 2016 04:09:58 +0000 (00:09 -0400)
ABS simplification from Iceman1001

armsrc/appmain.c
armsrc/iso14443b.c
armsrc/iso15693.c
armsrc/pcf7931.c
common/lfdemod.c
include/common.h

index 782c57fab10aa4371ce60d3ae64424bf81975874..d20b08b26326f45e0a525eb43f8151018085474d 100644 (file)
@@ -36,8 +36,6 @@
  #include "iso14443a.h"
 #endif
 
-#define abs(x) ( ((x)<0) ? -(x) : (x) )
-
 //=============================================================================
 // A buffer where we can queue things up to be sent through the FPGA, for
 // any purpose (fake tag, as reader, whatever). We go MSB first, since that
@@ -841,7 +839,7 @@ void ListenReaderField(int limit)
 
                if (limit != HF_ONLY) {
                        if(mode == 1) {
-                               if (abs(lf_av - lf_baseline) > REPORT_CHANGE) 
+                               if (ABS(lf_av - lf_baseline) > REPORT_CHANGE) 
                                        LED_D_ON();
                                else
                                        LED_D_OFF();
@@ -849,7 +847,7 @@ void ListenReaderField(int limit)
 
                        lf_av_new = AvgAdc(ADC_CHAN_LF);
                        // see if there's a significant change
-                       if(abs(lf_av - lf_av_new) > REPORT_CHANGE) {
+                       if(ABS(lf_av - lf_av_new) > REPORT_CHANGE) {
                                Dbprintf("LF 125/134kHz Field Change: %5dmV", (MAX_ADC_LF_VOLTAGE * lf_av_new) >> 10);
                                lf_av = lf_av_new;
                                if (lf_av > lf_max)
@@ -859,7 +857,7 @@ void ListenReaderField(int limit)
 
                if (limit != LF_ONLY) {
                        if (mode == 1){
-                               if (abs(hf_av - hf_baseline) > REPORT_CHANGE)   
+                               if (ABS(hf_av - hf_baseline) > REPORT_CHANGE)   
                                        LED_B_ON();
                                else
                                        LED_B_OFF();
@@ -867,7 +865,7 @@ void ListenReaderField(int limit)
 
                        hf_av_new = AvgAdc(ADC_CHAN_HF);
                        // see if there's a significant change
-                       if(abs(hf_av - hf_av_new) > REPORT_CHANGE) {
+                       if(ABS(hf_av - hf_av_new) > REPORT_CHANGE) {
                                Dbprintf("HF 13.56MHz Field Change: %5dmV", (MAX_ADC_HF_VOLTAGE * hf_av_new) >> 10);
                                hf_av = hf_av_new;
                                if (hf_av > hf_max)
index 82e5dd6a1c1bba44a33814b62b06be2d1e047093..22227e74bec96651d5c2620dd37f4bea210f27d2 100644 (file)
@@ -547,15 +547,20 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
        }
  */
 // Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by max(abs(ci),abs(cq)) + 1/2*min(abs(ci),abs(cq)))
+
+       //note: couldn't we just use MAX(ABS(ci),ABS(cq)) + (MIN(ABS(ci),ABS(cq))/2) from common.h - marshmellow
 #define CHECK_FOR_SUBCARRIER() { \
+               v = MAX(ABS(ci),ABS(cq)) + (MIN(ABS(ci),ABS(cq))/2); \
+       }
+               /*
                if(ci < 0) { \
-                       if(cq < 0) { /* ci < 0, cq < 0 */ \
+                       if(cq < 0) { \ // ci < 0, cq < 0
                                if (cq < ci) { \
                                        v = -cq - (ci >> 1); \
                                } else { \
                                        v = -ci - (cq >> 1); \
                                } \
-                       } else {        /* ci < 0, cq >= 0 */ \
+                       } else {        \ // ci < 0, cq >= 0
                                if (cq < -ci) { \
                                        v = -ci + (cq >> 1); \
                                } else { \
@@ -563,13 +568,13 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
                                } \
                        } \
                } else { \
-                       if(cq < 0) { /* ci >= 0, cq < 0 */ \
+                       if(cq < 0) { \ // ci >= 0, cq < 0
                                if (-cq < ci) { \
                                        v = ci - (cq >> 1); \
                                } else { \
                                        v = -cq + (ci >> 1); \
                                } \
-                       } else {        /* ci >= 0, cq >= 0 */ \
+                       } else {        \ // ci >= 0, cq >= 0
                                if (cq < ci) { \
                                        v = ci + (cq >> 1); \
                                } else { \
@@ -578,6 +583,7 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
                        } \
                } \
        }
+               */
 
        switch(Demod.state) {
                case DEMOD_UNSYNCD:
index e7145c5c9e84b3d6dd5399c145e74123e72be077..9a6ef9f01220a5d52fe441b7e16ae82e70affcb7 100644 (file)
@@ -319,18 +319,7 @@ static int GetIso15693AnswerFromTag(uint8_t *receivedResponse, int maxLen, int *
                        // every other is Q. We just want power, so abs(I) + abs(Q) is
                        // close to what we want.
                        if(getNext) {
-                               int8_t r;
-
-                               if(b < 0) {
-                                       r = -b;
-                               } else {
-                                       r = b;
-                               }
-                               if(prev < 0) {
-                                       r -= prev;
-                               } else {
-                                       r += prev;
-                               }
+                               int8_t r = ABS(b) + ABS(prev);
 
                                dest[c++] = (uint8_t)r;
 
@@ -468,18 +457,7 @@ static int GetIso15693AnswerFromSniff(uint8_t *receivedResponse, int maxLen, int
                        // every other is Q. We just want power, so abs(I) + abs(Q) is
                        // close to what we want.
                        if(getNext) {
-                               int8_t r;
-
-                               if(b < 0) {
-                                       r = -b;
-                               } else {
-                                       r = b;
-                               }
-                               if(prev < 0) {
-                                       r -= prev;
-                               } else {
-                                       r += prev;
-                               }
+                               int8_t r = ABS(b) + ABS(prev);
 
                                dest[c++] = (uint8_t)r;
 
@@ -648,18 +626,7 @@ void AcquireRawAdcSamplesIso15693(void)
                        // every other is Q. We just want power, so abs(I) + abs(Q) is
                        // close to what we want.
                        if(getNext) {
-                               int8_t r;
-
-                               if(b < 0) {
-                                       r = -b;
-                               } else {
-                                       r = b;
-                               }
-                               if(prev < 0) {
-                                       r -= prev;
-                               } else {
-                                       r += prev;
-                               }
+                               int8_t r = ABS(b) + ABS(prev);
 
                                dest[c++] = (uint8_t)r;
 
@@ -713,18 +680,7 @@ void RecordRawAdcSamplesIso15693(void)
                        // every other is Q. We just want power, so abs(I) + abs(Q) is
                        // close to what we want.
                        if(getNext) {
-                               int8_t r;
-
-                               if(b < 0) {
-                                       r = -b;
-                               } else {
-                                       r = b;
-                               }
-                               if(prev < 0) {
-                                       r -= prev;
-                               } else {
-                                       r += prev;
-                               }
+                               int8_t r = ABS(b) + ABS(prev);
 
                                dest[c++] = (uint8_t)r;
 
index 165319ca004e17a664511fa4d832a07d002c54fa..f9f33c5319fc8a01ad5c6da88f38817c9e2e8ade 100644 (file)
@@ -7,9 +7,6 @@
 #define T0_PCF 8 //period for the pcf7931 in us
 #define ALLOC 16
 
-#define abs(x) ( ((x)<0) ? -(x) : (x) )
-#define max(x,y) ( x<y ? y:x)
-
 int DemodPCF7931(uint8_t **outBlocks) {
 
     uint8_t bits[256] = {0x00};
@@ -72,7 +69,7 @@ int DemodPCF7931(uint8_t **outBlocks) {
 
                        // Switch depending on lc length:
                        // Tolerance is 1/8 of clock rate (arbitrary)
-                       if (abs(lc-clock/4) < tolerance) {
+                       if (ABS(lc-clock/4) < tolerance) {
                                // 16T0
                                if((i - pmc) == lc) { /* 16T0 was previous one */
                                        /* It's a PMC ! */
@@ -84,7 +81,7 @@ int DemodPCF7931(uint8_t **outBlocks) {
                                else {
                                        pmc = i;
                                }
-                       } else if (abs(lc-clock/2) < tolerance) {
+                       } else if (ABS(lc-clock/2) < tolerance) {
                                // 32TO
                                if((i - pmc) == lc) { /* 16T0 was previous one */
                                        /* It's a PMC ! */
@@ -99,7 +96,7 @@ int DemodPCF7931(uint8_t **outBlocks) {
                                }
                                else
                                        half_switch++;
-                       } else if (abs(lc-clock) < tolerance) {
+                       } else if (ABS(lc-clock) < tolerance) {
                                // 64TO
                 bits[bitidx++] = 1;
                        } else {
@@ -204,7 +201,7 @@ void ReadPCF7931() {
                                                Blocks[0][ALLOC] = 1;
                                                memcpy(Blocks[1], tmpBlocks[i+1], 16);
                                                Blocks[1][ALLOC] = 1;
-                                               max_blocks = max((Blocks[1][14] & 0x7f), Blocks[1][15]) + 1;
+                                               max_blocks = MAX((Blocks[1][14] & 0x7f), Blocks[1][15]) + 1;
                                                // Debug print
                                                Dbprintf("(dbg) Max blocks: %d", max_blocks);
                                                num_blocks = 2;
index d6c024fab9bfa872d9a210fa9dfb9334453e6aca..cf11b25b8d1ea28fef82c7622ba526f54e78b99c 100644 (file)
@@ -262,9 +262,9 @@ void askAmp(uint8_t *BitStream, size_t size)
 {
        for(size_t i = 1; i<size; i++){
                if (BitStream[i]-BitStream[i-1]>=30) //large jump up
-                       BitStream[i]=127;
+                       BitStream[i]=255;
                else if(BitStream[i]-BitStream[i-1]<=-20) //large jump down
-                       BitStream[i]=-127;
+                       BitStream[i]=0;
        }
        return;
 }
@@ -464,10 +464,10 @@ int gProxII_Demod(uint8_t BitStream[], size_t *size)
                //return start position
                return (int) startIdx;
        }
-       return -5;
+       return -5; //spacer bits not found - not a valid gproxII
 }
 
-//translate wave to 11111100000 (1 for each short wave 0 for each long wave)
+//translate wave to 11111100000 (1 for each short wave [higher freq] 0 for each long wave [lower freq])
 size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow)
 {
        size_t last_transition = 0;
@@ -491,6 +491,7 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow
        // count cycles between consecutive lo-hi transitions, there should be either 8 (fc/8)
        // or 10 (fc/10) cycles but in practice due to noise etc we may end up with anywhere
        // between 7 to 11 cycles so fuzz it by treat anything <9 as 8 and anything else as 10
+       //  (could also be fc/5 && fc/7 for fsk1 = 4-9)
        for(idx = 161; idx < size-20; idx++) {
                // threshold current value
 
@@ -498,23 +499,24 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow
                else dest[idx] = 1;
 
                // Check for 0->1 transition
-               if (dest[idx-1] < dest[idx]) { // 0 -> 1 transition
+               if (dest[idx-1] < dest[idx]) {
                        preLastSample = LastSample;
                        LastSample = currSample;
                        currSample = idx-last_transition;
-                       if (currSample < (fclow-2)){            //0-5 = garbage noise (or 0-3)
+                       if (currSample < (fclow-2)) {                   //0-5 = garbage noise (or 0-3)
                                //do nothing with extra garbage
-                       } else if (currSample < (fchigh-1)) { //6-8 = 8 sample waves  or 3-6 = 5
+                       } else if (currSample < (fchigh-1)) {           //6-8 = 8 sample waves  (or 3-6 = 5)
+                               //correct previous 9 wave surrounded by 8 waves (or 6 surrounded by 5)
                                if (LastSample > (fchigh-2) && (preLastSample < (fchigh-1) || preLastSample     == 0 )){
-                                       dest[numBits-1]=1;  //correct previous 9 wave surrounded by 8 waves
+                                       dest[numBits-1]=1;
                                }
                                dest[numBits++]=1;
 
-                       } else if (currSample > (fchigh) && !numBits) { //12 + and first bit = garbage 
+                       } else if (currSample > (fchigh) && !numBits) { //12 + and first bit = unusable garbage 
                                //do nothing with beginning garbage
-                       } else if (currSample == (fclow+1) && LastSample == (fclow-1)) { // had a 7 then a 9 should be two 8's
+                       } else if (currSample == (fclow+1) && LastSample == (fclow-1)) { // had a 7 then a 9 should be two 8's (or 4 then a 6 should be two 5's)
                                dest[numBits++]=1;
-                       } else {                                         //9+ = 10 sample waves
+                       } else {                                        //9+ = 10 sample waves (or 6+ = 7)
                                dest[numBits++]=0;
                        }
                        last_transition = idx;
@@ -524,6 +526,7 @@ size_t fsk_wave_demod(uint8_t * dest, size_t size, uint8_t fchigh, uint8_t fclow
 }
 
 //translate 11111100000 to 10
+//rfLen = clock, fchigh = larger field clock, fclow = smaller field clock
 size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen,
                uint8_t invert, uint8_t fchigh, uint8_t fclow)
 {
@@ -533,8 +536,9 @@ size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen,
        uint32_t n=1;
        for( idx=1; idx < size; idx++) {
                n++;
-               if (dest[idx]==lastval) continue; 
+               if (dest[idx]==lastval) continue; //skip until we hit a transition
                
+               //find out how many bits (n) we collected
                //if lastval was 1, we have a 1->0 crossing
                if (dest[idx-1]==1) {
                        n = (n * fclow + rfLen/2) / rfLen;
@@ -543,6 +547,7 @@ size_t aggregate_bits(uint8_t *dest, size_t size, uint8_t rfLen,
                }
                if (n == 0) n = 1;
 
+               //add to our destination the bits we collected          
                memset(dest+numBits, dest[idx-1]^invert , n);
                numBits += n;
                n=0;
@@ -1495,8 +1500,8 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert)
        numBits += (firstFullWave / *clock);
        //set start of wave as clock align
        lastClkBit = firstFullWave;
-       //PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen);  
-       //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d", *clock, lastClkBit);
+       if (g_debugMode==2) prnt("DEBUG PSK: firstFullWave: %u, waveLen: %u",firstFullWave,fullWaveLen);  
+       if (g_debugMode==2) prnt("DEBUG: clk: %d, lastClkBit: %u, fc: %u", *clock, lastClkBit,(unsigned int) fc);
        waveStart = 0;
        dest[numBits++] = curPhase; //set first read bit
        for (i = firstFullWave + fullWaveLen - 1; i < *size-3; i++){
@@ -1679,7 +1684,7 @@ bool DetectST(uint8_t buffer[], size_t *size, int *foundclock) {
        i=0;
        // warning - overwriting buffer given with raw wave data with ST removed...
        while ( dataloc < bufsize-(clk/2) ) {
-               //compensate for long high at end of ST not being high... (we cut out the high part)
+               //compensate for long high at end of ST not being high due to signal loss... (and we cut out the start of wave high part)
                if (buffer[dataloc]<high && buffer[dataloc]>low && buffer[dataloc+3]<high && buffer[dataloc+3]>low) {
                        for(i=0; i < clk/2-tol; ++i) {
                                buffer[dataloc+i] = high+5;
@@ -1694,7 +1699,7 @@ bool DetectST(uint8_t buffer[], size_t *size, int *foundclock) {
                        }
                }
                newloc += i;
-               //skip next ST
+               //skip next ST  -  we just assume it will be there from now on...
                dataloc += clk*4;
        }
        *size = newloc;
index feed109c2dfe3faa216edb89fd0852100b542896..998db64dccc7820493dbb3df1042562e7b613ef1 100644 (file)
@@ -24,6 +24,10 @@ typedef unsigned char byte_t;
 #ifndef MAX
 # define MAX(a, b) (((a) > (b)) ? (a) : (b))
 #endif
+#ifndef ABS
+# define ABS(a) ( ((a)<0) ? -(a) : (a) )
+#endif
+
 
 #define RAMFUNC __attribute((long_call, section(".ramfunc")))
 
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