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CHG: 'lf em4x' - the em4x50 demod didn't calc ASKDemod_ext with a refenence bool.

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CHG:  'lf em4x' - refactored the code for emd4x50 demod
This commit is contained in:
iceman1001 2017-02-16 16:38:09 +01:00
commit bd09006a8c
3 changed files with 93 additions and 120 deletions
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207
client/cmdlfem4x.c
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@ -514,10 +514,10 @@ int usage_lf_em_read(void) {
}
//search for given preamble in given BitStream and return success=1 or fail=0 and startIndex
uint8_t EMpreambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t size, size_t *startIdx)
{
uint8_t EMpreambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t size, size_t *startIdx) {
// Sanity check. If preamble length is bigger than bitstream length.
if ( size <= pLen ) return 0;
// em only sends preamble once, so look for it once in the first x bits
uint8_t foundCnt = 0;
for (int idx = 0; idx < size - pLen; idx++){
@ -533,127 +533,100 @@ uint8_t EMpreambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, siz
return 0;
}
#define EM_PREAMBLE_LEN 6
bool detectFSK(){
// detect fsk clock
if (!GetFskClock("", FALSE, FALSE)) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: FSK clock failed");
return FALSE;
}
// demod
int ans = FSKrawDemod("0 0", FALSE);
if (!ans) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: FSK Demod failed");
return FALSE;
}
return TRUE;
}
// PSK clocks should be easy to detect ( but difficult to demod a non-repeating pattern... )
bool detectPSK(){
int ans = GetPskClock("", FALSE, FALSE);
if (!ans) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: PSK clock failed");
return FALSE;
}
PrintAndLog("PSK response possibly found, run `data rawd p1` to attempt to demod");
return TRUE;
}
// try manchester - NOTE: ST only applies to T55x7 tags.
bool detectASK_MAN(){
bool stcheck = FALSE;
int ans = ASKDemod_ext("0 0 0", TRUE, FALSE, 1, &stcheck);
if (!ans) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: ASK/Manchester Demod failed");
return FALSE;
}
return TRUE;
}
bool detectASK_BI(){
int ans = ASKbiphaseDemod("0 0 1", FALSE);
if (!ans) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: ASK/biphase normal demod failed");
ans = ASKbiphaseDemod("0 1 1", FALSE);
if (!ans) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: ASK/biphase inverted demod failed");
return FALSE;
}
}
return TRUE;
}
bool doPreambleSearch(size_t *startIdx){
// skip first two 0 bits as they might have been missed in the demod
uint8_t preamble[EM_PREAMBLE_LEN] = {0,0,1,0,1,0};
// set size to 10 to only test first 4 positions for the preamble
size_t size = (10 > DemodBufferLen) ? DemodBufferLen : 10;
*startIdx = 0;
if (g_debugMode) PrintAndLog("Before:: startindex: %u | size: %u", *startIdx, size);
uint8_t errChk = !EMpreambleSearch(DemodBuffer, preamble, EM_PREAMBLE_LEN, size, startIdx);
if ( errChk == 0) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305 preamble not found :: %d", *startIdx);
return FALSE;
}
if (g_debugMode) PrintAndLog("After:: startindex: %u | size: %u", *startIdx, size);
return TRUE;
}
// FSK, PSK, ASK/MANCHESTER, ASK/BIPHASE, ASK/DIPHASE
// should cover 90% of known used configs
// the rest will need to be manually demoded for now...
int demodEM4x05resp(uint8_t bitsNeeded) {
int ans = 0;
bool demodFound = false;
DemodBufferLen = 0x00;
// skip first two 0 bits as they might have been missed in the demod
uint8_t preamble[6] = {0,0,1,0,1,0};
// test for FSK wave (easiest to 99% ID)
if (GetFskClock("", FALSE, FALSE)) {
//valid fsk clocks found
ans = FSKrawDemod("0 0", false);
if (!ans) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: FSK Demod failed");
} else {
// set size to 10 to only test first 4 positions for the preamble
size_t size = (10 > DemodBufferLen) ? DemodBufferLen : 10;
size_t startIdx = 0;
size_t startIdx = 0;
if (detectASK_MAN() && doPreambleSearch( &startIdx ))
goto EXIT_SET;
if (detectASK_BI() && doPreambleSearch( &startIdx ))
goto EXIT_SET;
if (detectFSK() && doPreambleSearch( &startIdx ))
goto EXIT_SET;
if (g_debugMode) PrintAndLog("ANS: %d | %u | %u", ans, startIdx, size);
if (detectPSK() && doPreambleSearch( &startIdx ))
goto EXIT_SET;
return -1;
uint8_t errChk = !EMpreambleSearch(DemodBuffer, preamble, sizeof(preamble), size, &startIdx);
if ( errChk == 0) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305 preamble not found :: %d", startIdx);
} else {
//can't test size because the preamble doesn't repeat :(
//meaning chances of false positives are high.
demodFound = true;
}
}
}
// PSK clocks should be easy to detect ( but difficult to demod a non-repeating pattern... )
if (!demodFound) {
ans = GetPskClock("", FALSE, FALSE);
if (ans>0) {
PrintAndLog("PSK response possibly found, run `data rawd p1` to attempt to demod");
}
}
// more common than biphase
if (!demodFound) {
DemodBufferLen = 0x00;
// try manchester - NOTE: ST only applies to T55x7 tags.
ans = ASKDemod_ext("0,0,1", false, false, 1, false);
if (!ans) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: ASK/Manchester Demod failed");
} else {
// set size to 10 to only test first 4 positions for the preamble
size_t size = (10 > DemodBufferLen) ? DemodBufferLen : 10;
size_t startIdx = 0;
if (g_debugMode) PrintAndLog("ANS: %d | %u | %u", ans, startIdx, size);
uint8_t errChk = !EMpreambleSearch(DemodBuffer, preamble, sizeof(preamble), size, &startIdx);
if ( errChk == 0) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305 preamble not found :: %d", startIdx);
} else {
//can't test size because the preamble doesn't repeat :(
//meaning chances of false positives are high.
demodFound = true;
}
}
}
if (!demodFound) {
DemodBufferLen = 0x00;
//try biphase
ans = ASKbiphaseDemod("0 0 1", FALSE);
if (!ans) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: ASK/biphase Demod failed");
//return -1;
} else {
// set size to 10 to only test first 4 positions for the preamble
size_t size = (10 > DemodBufferLen) ? DemodBufferLen : 10;
size_t startIdx = 0;
if (g_debugMode) PrintAndLog("ANS: %d | %u | %u", ans, startIdx, size);
uint8_t errChk = !EMpreambleSearch(DemodBuffer, preamble, sizeof(preamble), size, &startIdx);
if ( errChk == 0) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305 preamble not found :: %d", startIdx);
//return -1;
} else {
//can't test size because the preamble doesn't repeat :(
//meaning chances of false positives are high.
demodFound = true;
}
}
}
if (!demodFound) {
DemodBufferLen = 0x00;
//try diphase (differential biphase or inverted)
ans = ASKbiphaseDemod("0 1 1", FALSE);
if (!ans) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: ASK/biphase Demod failed");
} else {
// set size to 10 to only test first 4 positions for the preamble
size_t size = (10 > DemodBufferLen) ? DemodBufferLen : 10;
size_t startIdx = 0;
if (g_debugMode) PrintAndLog("ANS: %d | %u | %u", ans, startIdx, size);
uint8_t errChk = !EMpreambleSearch(DemodBuffer, preamble, sizeof(preamble), size, &startIdx);
if ( errChk == 0) {
if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305 preamble not found :: %d", startIdx);
} else {
//can't test size because the preamble doesn't repeat :(
//meaning chances of false positives are high.
demodFound = true;
}
}
}
if (demodFound && bitsNeeded < DemodBufferLen) {
if (bitsNeeded > 0) {
setDemodBuf(DemodBuffer + ans + sizeof(preamble), bitsNeeded, 0);
EXIT_SET:
if ( bitsNeeded < DemodBufferLen) {
setDemodBuf(DemodBuffer + startIdx + EM_PREAMBLE_LEN, bitsNeeded, 0);
CmdPrintDemodBuff("x");
}
return 1;
}
return -1;
@ -734,7 +707,6 @@ int CmdWriteWord(const char *Cmd) {
data = param_get32ex(Cmd, 1, -1, 16);
pwd = param_get32ex(Cmd, 2, -1, 16);
if ( (addr > 15) || (addr < 0 ) || ( addr == -1) ) {
PrintAndLog("Address must be between 0 and 15");
return 1;
@ -760,7 +732,7 @@ int CmdWriteWord(const char *Cmd) {
//get response if there is one
uint8_t got[6000]; // 8 bit preamble + 32 bit word response (max clock (128) * 40bits = 5120 samples)
GetFromBigBuf(got, sizeof(got), 0);
if ( !WaitForResponseTimeout(CMD_ACK, NULL, 8000) ) {
if ( !WaitForResponseTimeout(CMD_ACK, NULL, 2500) ) {
PrintAndLog("command execution time out");
return -2;
}
@ -775,7 +747,6 @@ int CmdWriteWord(const char *Cmd) {
PrintAndLog("Write Verified");
}
return result;
return 0;
}
static command_t CommandTable[] = {