int CmdEMdemodASK(const char *Cmd)
{
char cmdp = param_getchar(Cmd, 0);
- int findone = (cmdp == '1') ? 1 : 0;
+ int findone = (cmdp == '1') ? 1 : 0;
UsbCommand c={CMD_EM410X_DEMOD};
c.arg[0]=findone;
SendCommand(&c);
{
if (rows*cols>size) return false;
uint8_t colP=0;
- //assume last row is a parity row and do not test
+ //assume last col is a parity and do not test
for (uint8_t colNum = 0; colNum < cols-1; colNum++) {
for (uint8_t rowNum = 0; rowNum < rows; rowNum++) {
colP ^= BitStream[(rowNum*cols)+colNum];
code = code<<8 | bytebits_to_byte(BitStream+27,8);
if (verbose || g_debugMode){
for (uint8_t i = 0; i<5; i++){
- if (i == 4) PrintAndLog("");
+ if (i == 4) PrintAndLog(""); //parity byte spacer
PrintAndLog("%d%d%d%d%d%d%d%d %d -> 0x%02x",
BitStream[i*9],
BitStream[i*9+1],
else
PrintAndLog("Parity Failed");
}
- //PrintAndLog("Code: %08x",code);
return code;
}
/* Read the transmitted data of an EM4x50 tag
* is stored in the blocks defined in the control word First and Last
* Word Read values. UID is stored in block 32.
*/
+ //completed by Marshmellow
int EM4x50Read(const char *Cmd, bool verbose)
{
- uint8_t fndClk[]={0,8,16,32,40,50,64};
+ uint8_t fndClk[] = {8,16,32,40,50,64,128};
int clk = 0;
int invert = 0;
- sscanf(Cmd, "%i %i", &clk, &invert);
int tol = 0;
int i, j, startblock, skip, block, start, end, low, high, minClk;
- bool complete= false;
+ bool complete = false;
int tmpbuff[MAX_GRAPH_TRACE_LEN / 64];
- save_restoreGB(1);
uint32_t Code[6];
char tmp[6];
-
char tmp2[20];
- high= low= 0;
+ high = low = 0;
memset(tmpbuff, 0, MAX_GRAPH_TRACE_LEN / 64);
-
+
+ // get user entry if any
+ sscanf(Cmd, "%i %i", &clk, &invert);
+
+ // save GraphBuffer - to restore it later
+ save_restoreGB(1);
+
// first get high and low values
- for (i = 0; i < GraphTraceLen; i++)
- {
+ for (i = 0; i < GraphTraceLen; i++) {
if (GraphBuffer[i] > high)
high = GraphBuffer[i];
else if (GraphBuffer[i] < low)
low = GraphBuffer[i];
}
- // populate a buffer with pulse lengths
- i= 0;
- j= 0;
- minClk= 255;
- while (i < GraphTraceLen)
- {
+ i = 0;
+ j = 0;
+ minClk = 255;
+ // get to first full low to prime loop and skip incomplete first pulse
+ while ((GraphBuffer[i] < high) && (i < GraphTraceLen))
+ ++i;
+ while ((GraphBuffer[i] > low) && (i < GraphTraceLen))
+ ++i;
+ skip = i;
+
+ // populate tmpbuff buffer with pulse lengths
+ while (i < GraphTraceLen) {
// measure from low to low
- while ((GraphBuffer[i] > low) && (i<GraphTraceLen))
+ while ((GraphBuffer[i] > low) && (i < GraphTraceLen))
++i;
start= i;
- while ((GraphBuffer[i] < high) && (i<GraphTraceLen))
+ while ((GraphBuffer[i] < high) && (i < GraphTraceLen))
++i;
- while ((GraphBuffer[i] > low) && (i<GraphTraceLen))
+ while ((GraphBuffer[i] > low) && (i < GraphTraceLen))
++i;
if (j>=(MAX_GRAPH_TRACE_LEN/64)) {
break;
}
tmpbuff[j++]= i - start;
- if (i-start < minClk) minClk = i-start;
+ if (i-start < minClk && i < GraphTraceLen) {
+ minClk = i - start;
+ }
}
// set clock
- if (!clk){
+ if (!clk) {
for (uint8_t clkCnt = 0; clkCnt<7; clkCnt++) {
tol = fndClk[clkCnt]/8;
- if (fndClk[clkCnt]-tol >= minClk) {
+ if (minClk >= fndClk[clkCnt]-tol && minClk <= fndClk[clkCnt]+1) {
clk=fndClk[clkCnt];
break;
}
}
+ if (!clk) return 0;
} else tol = clk/8;
// look for data start - should be 2 pairs of LW (pulses of clk*3,clk*2)
- start= -1;
- skip= 0;
- for (i= 0; i < j - 4 ; ++i)
- {
+ start = -1;
+ for (i= 0; i < j - 4 ; ++i) {
skip += tmpbuff[i];
- if (tmpbuff[i] >= clk*3-tol && tmpbuff[i] <= clk*3+tol)
- if (tmpbuff[i+1] >= clk*2-tol && tmpbuff[i+1] <= clk*2+tol)
- if (tmpbuff[i+2] >= clk*3-tol && tmpbuff[i+2] <= clk*3+tol)
- if (tmpbuff[i+3] >= clk-tol)
+ if (tmpbuff[i] >= clk*3-tol && tmpbuff[i] <= clk*3+tol) //3 clocks
+ if (tmpbuff[i+1] >= clk*2-tol && tmpbuff[i+1] <= clk*2+tol) //2 clocks
+ if (tmpbuff[i+2] >= clk*3-tol && tmpbuff[i+2] <= clk*3+tol) //3 clocks
+ if (tmpbuff[i+3] >= clk-tol) //1.5 to 2 clocks - depends on bit following
{
start= i + 4;
break;
}
}
- startblock= i + 4;
+ startblock = i + 4;
// skip over the remainder of LW
skip += tmpbuff[i+1] + tmpbuff[i+2] + clk + clk/8;
-
int phaseoff = tmpbuff[i+3]-clk;
// now do it again to find the end
end = skip;
- for (i += 3; i < j - 4 ; ++i)
- {
+ for (i += 3; i < j - 4 ; ++i) {
end += tmpbuff[i];
- if (tmpbuff[i] >= clk*3-tol && tmpbuff[i] <= clk*3 + tol)
- if (tmpbuff[i+1] >= clk*2-tol && tmpbuff[i+1] <= clk*2 + tol)
- if (tmpbuff[i+2] >= clk*3-tol && tmpbuff[i+2] <= clk*3 + tol)
- if (tmpbuff[i+3] >= clk-tol)
+ if (tmpbuff[i] >= clk*3-tol && tmpbuff[i] <= clk*3+tol) //3 clocks
+ if (tmpbuff[i+1] >= clk*2-tol && tmpbuff[i+1] <= clk*2+tol) //2 clocks
+ if (tmpbuff[i+2] >= clk*3-tol && tmpbuff[i+2] <= clk*3+tol) //3 clocks
+ if (tmpbuff[i+3] >= clk-tol) //1.5 to 2 clocks - depends on bit following
{
complete= true;
break;
// report back
if (verbose || g_debugMode) {
if (start >= 0) {
- PrintAndLog("\nNote: should print 45 bits then 0177 (end of block)");
- PrintAndLog(" for each block");
- PrintAndLog(" Also, sometimes the demod gets out of sync and ");
- PrintAndLog(" inverts the output - when this happens the 0177");
- PrintAndLog(" will be 3 extra 1's at the end");
- PrintAndLog(" 'data askedge' command may fix that");
+ PrintAndLog("\nNote: one block = 50 bits (32 data, 12 parity, 6 marker)");
} else {
- PrintAndLog("No data found!");
+ PrintAndLog("No data found!, clock tried:%d",clk);
PrintAndLog("Try again with more samples.");
+ PrintAndLog(" or after a 'data askedge' command to clean up the read");
return 0;
}
if (!complete)
PrintAndLog("Try again with more samples.");
}
} else if (start < 0) return 0;
- start=skip;
+ start = skip;
snprintf(tmp2, sizeof(tmp2),"%d %d 1000 %d", clk, invert, clk*47);
// get rid of leading crap
- snprintf(tmp, sizeof(tmp),"%i",skip);
+ snprintf(tmp, sizeof(tmp), "%i", skip);
CmdLtrim(tmp);
bool pTest;
- bool AllPTest=true;
+ bool AllPTest = true;
// now work through remaining buffer printing out data blocks
block = 0;
i = startblock;
- while (block < 6)
- {
+ while (block < 6) {
if (verbose || g_debugMode) PrintAndLog("\nBlock %i:", block);
skip = phaseoff;
// look for LW before start of next block
- for ( ; i < j - 4 ; ++i)
- {
+ for ( ; i < j - 4 ; ++i) {
skip += tmpbuff[i];
if (tmpbuff[i] >= clk*3-tol && tmpbuff[i] <= clk*3+tol)
if (tmpbuff[i+1] >= clk-tol)
skip += clk;
phaseoff = tmpbuff[i+1]-clk;
i += 2;
- if (ASKmanDemod(tmp2, false, false)<1) return 0;
+ if (ASKmanDemod(tmp2, false, false) < 1) {
+ save_restoreGB(0);
+ return 0;
+ }
//set DemodBufferLen to just one block
DemodBufferLen = skip/clk;
//test parities
pTest &= EM_EndParityTest(DemodBuffer,DemodBufferLen,5,9,0);
AllPTest &= pTest;
//get output
- Code[block]=OutputEM4x50_Block(DemodBuffer,DemodBufferLen,verbose, pTest);
- if (g_debugMode) PrintAndLog("\nskipping %d samples, bits:%d",start, skip/clk);
+ Code[block] = OutputEM4x50_Block(DemodBuffer,DemodBufferLen,verbose, pTest);
+ if (g_debugMode) PrintAndLog("\nskipping %d samples, bits:%d", skip, skip/clk);
//skip to start of next block
snprintf(tmp,sizeof(tmp),"%i",skip);
CmdLtrim(tmp);
block++;
- if (i>=end) break; //in case chip doesn't output 6 blocks
+ if (i >= end) break; //in case chip doesn't output 6 blocks
}
//print full code:
if (verbose || g_debugMode || AllPTest){
- PrintAndLog("Found data at sample: %i - using clock: %i",skip,clk);
- //PrintAndLog("\nSummary:");
- end=block;
- for (block=0; block<end; block++){
+ PrintAndLog("Found data at sample: %i - using clock: %i", start, clk);
+ end = block;
+ for (block=0; block < end; block++){
PrintAndLog("Block %d: %08x",block,Code[block]);
}
if (AllPTest)
PrintAndLog("Parities Passed");
else
PrintAndLog("Parities Failed");
+ PrintAndLog("Try cleaning the read samples with 'data askedge'");
}
//restore GraphBuffer
projects / proxmark3-svn / blobdiff