- int i,j, bitindex, lc, tolerance, warnings;
- warnings = 0;
- int upperlimit = len*2/clock+8;
- i = startIndex;
- j = 0;
- tolerance = clock/4;
- uint8_t decodedArr[len];
-
- /* Detect duration between 2 successive transitions */
- for (bitindex = 1; i < len; i++) {
-
- if (data[i-1] != data[i]) {
- lc = i - startIndex;
- startIndex = i;
-
- // Error check: if bitindex becomes too large, we do not
- // have a Manchester encoded bitstream or the clock is really wrong!
- if (bitindex > upperlimit ) {
- PrintAndLog("Error: the clock you gave is probably wrong, aborting.");
- return 0;
- }
- // Then switch depending on lc length:
- // Tolerance is 1/4 of clock rate (arbitrary)
- if (abs((lc-clock)/2) < tolerance) {
- // Short pulse : either "1" or "0"
- decodedArr[bitindex++] = data[i-1];
- } else if (abs(lc-clock) < tolerance) {
- // Long pulse: either "11" or "00"
- decodedArr[bitindex++] = data[i-1];
- decodedArr[bitindex++] = data[i-1];
- } else {
- ++warnings;
- PrintAndLog("Warning: Manchester decode error for pulse width detection.");
- if (warnings > 10) {
- PrintAndLog("Error: too many detection errors, aborting.");
- return 0;
- }
- }
- }
- }
-
- /*
- * We have a decodedArr of "01" ("1") or "10" ("0")
- * parse it into final decoded dataout
- */
- for (i = 0; i < bitindex; i += 2) {
-
- if ((decodedArr[i] == 0) && (decodedArr[i+1] == 1)) {
- dataout[j++] = 1;
- } else if ((decodedArr[i] == 1) && (decodedArr[i+1] == 0)) {
- dataout[j++] = 0;
- } else {
- i++;
- warnings++;
- PrintAndLog("Unsynchronized, resync...");
- PrintAndLog("(too many of those messages mean the stream is not Manchester encoded)");
-
- if (warnings > 10) {
- PrintAndLog("Error: too many decode errors, aborting.");
- return 0;
- }
- }
- }
-
- PrintAndLog("%s", sprint_hex(dataout, j));
- return j;
- }
-
- void ManchesterDiffDecodedString(const uint8_t* bitstream, size_t len, uint8_t invert){
- /*
- * We have a bitstream of "01" ("1") or "10" ("0")
- * parse it into final decoded bitstream
- */
- int i, j, warnings;
- uint8_t decodedArr[(len/2)+1];
-
- j = warnings = 0;
-
- uint8_t lastbit = 0;
-
- for (i = 0; i < len; i += 2) {
-
- uint8_t first = bitstream[i];
- uint8_t second = bitstream[i+1];
-
- if ( first == second ) {
- ++i;
- ++warnings;
- if (warnings > 10) {
- PrintAndLog("Error: too many decode errors, aborting.");
- return;
- }
- }
- else if ( lastbit != first ) {
- decodedArr[j++] = 0 ^ invert;
- }
- else {
- decodedArr[j++] = 1 ^ invert;
- }
- lastbit = second;
- }
-
- PrintAndLog("%s", sprint_hex(decodedArr, j));
-}
-
-void PrintPaddedManchester( uint8_t* bitStream, size_t len, size_t blocksize){
-
- PrintAndLog(" Manchester decoded : %d bits", len);
-
- uint8_t mod = len % blocksize;
- uint8_t div = len / blocksize;
- int i;
-
- // Now output the bitstream to the scrollback by line of 16 bits
- for (i = 0; i < div*blocksize; i+=blocksize) {
- PrintAndLog(" %s", sprint_bin(bitStream+i,blocksize) );
- }
-
- if ( mod > 0 )
- PrintAndLog(" %s", sprint_bin(bitStream+i, mod) );
-}
-
-void iceFsk(int * data, const size_t len){
-
- //34359738 == 125khz (2^32 / 125) =
-
- // parameters
- float phase_offset = 0.00f; // carrier phase offset
- float frequency_offset = 0.30f; // carrier frequency offset
- float wn = 0.01f; // pll bandwidth
- float zeta = 0.707f; // pll damping factor
- float K = 1000; // pll loop gain
- size_t n = len; // number of samples
-
- // generate loop filter parameters (active PI design)
- float t1 = K/(wn*wn); // tau_1
- float t2 = 2*zeta/wn; // tau_2
-
- // feed-forward coefficients (numerator)
- float b0 = (4*K/t1)*(1.+t2/2.0f);
- float b1 = (8*K/t1);
- float b2 = (4*K/t1)*(1.-t2/2.0f);
-
- // feed-back coefficients (denominator)
- // a0 = 1.0 is implied
- float a1 = -2.0f;
- float a2 = 1.0f;
-
- // filter buffer
- float v0=0.0f, v1=0.0f, v2=0.0f;
-
- // initialize states
- float phi = phase_offset; // input signal's initial phase
- float phi_hat = 0.0f; // PLL's initial phase
-
- unsigned int i;
- float complex x,y;
- float complex output[n];
-
- for (i=0; i<n; i++) {
- // INPUT SIGNAL
- x = data[i];
- phi += frequency_offset;
-
- // generate complex sinusoid
- y = cosf(phi_hat) + _Complex_I*sinf(phi_hat);
-
- output[i] = y;
-
- // compute error estimate
- float delta_phi = cargf( x * conjf(y) );
-
-
- // print results to standard output
- printf(" %6u %12.8f %12.8f %12.8f %12.8f %12.8f\n",
- i,
- crealf(x), cimagf(x),
- crealf(y), cimagf(y),
- delta_phi);
-
- // push result through loop filter, updating phase estimate
-
- // advance buffer
- v2 = v1; // shift center register to upper register
- v1 = v0; // shift lower register to center register
-
- // compute new lower register
- v0 = delta_phi - v1*a1 - v2*a2;
-
- // compute new output
- phi_hat = v0*b0 + v1*b1 + v2*b2;
-
- }
-
- for (i=0; i<len; ++i){
- data[i] = (int)crealf(output[i]);
- }
-}
-
-/* Sliding DFT
- Smooths out
-*/
-void iceFsk2(int * data, const size_t len){
-
- int i, j;
- int output[len];
-
- // for (i=0; i<len-5; ++i){
- // for ( j=1; j <=5; ++j) {
- // output[i] += data[i*j];
- // }
- // output[i] /= 5;
- // }
- int rest = 127;
- int tmp =0;
- for (i=0; i<len; ++i){
- if ( data[i] < 127)
- output[i] = 0;
- else {
- tmp = (100 * (data[i]-rest)) / rest;
- output[i] = (tmp > 60)? 100:0;
- }
- }
-
- for (j=0; j<len; ++j)
- data[j] = output[j];
-}
-
projects / proxmark3-svn / blobdiff