+
+
+//-----------------------------------
+// EM4469 / EM4305 routines
+//-----------------------------------
+#define FWD_CMD_LOGIN 0xC //including the even parity, binary mirrored
+#define FWD_CMD_WRITE 0xA
+#define FWD_CMD_READ 0x9
+#define FWD_CMD_DISABLE 0x5
+
+
+uint8_t forwardLink_data[64]; //array of forwarded bits
+uint8_t * forward_ptr; //ptr for forward message preparation
+uint8_t fwd_bit_sz; //forwardlink bit counter
+uint8_t * fwd_write_ptr; //forwardlink bit pointer
+
+//====================================================================
+// prepares command bits
+// see EM4469 spec
+//====================================================================
+//--------------------------------------------------------------------
+uint8_t Prepare_Cmd( uint8_t cmd ) {
+//--------------------------------------------------------------------
+
+ *forward_ptr++ = 0; //start bit
+ *forward_ptr++ = 0; //second pause for 4050 code
+
+ *forward_ptr++ = cmd;
+ cmd >>= 1;
+ *forward_ptr++ = cmd;
+ cmd >>= 1;
+ *forward_ptr++ = cmd;
+ cmd >>= 1;
+ *forward_ptr++ = cmd;
+
+ return 6; //return number of emited bits
+}
+
+//====================================================================
+// prepares address bits
+// see EM4469 spec
+//====================================================================
+
+//--------------------------------------------------------------------
+uint8_t Prepare_Addr( uint8_t addr ) {
+//--------------------------------------------------------------------
+
+ register uint8_t line_parity;
+
+ uint8_t i;
+ line_parity = 0;
+ for(i=0;i<6;i++) {
+ *forward_ptr++ = addr;
+ line_parity ^= addr;
+ addr >>= 1;
+ }
+
+ *forward_ptr++ = (line_parity & 1);
+
+ return 7; //return number of emited bits
+}
+
+//====================================================================
+// prepares data bits intreleaved with parity bits
+// see EM4469 spec
+//====================================================================
+
+//--------------------------------------------------------------------
+uint8_t Prepare_Data( uint16_t data_low, uint16_t data_hi) {
+//--------------------------------------------------------------------
+
+ register uint8_t line_parity;
+ register uint8_t column_parity;
+ register uint8_t i, j;
+ register uint16_t data;
+
+ data = data_low;
+ column_parity = 0;
+
+ for(i=0; i<4; i++) {
+ line_parity = 0;
+ for(j=0; j<8; j++) {
+ line_parity ^= data;
+ column_parity ^= (data & 1) << j;
+ *forward_ptr++ = data;
+ data >>= 1;
+ }
+ *forward_ptr++ = line_parity;
+ if(i == 1)
+ data = data_hi;
+ }
+
+ for(j=0; j<8; j++) {
+ *forward_ptr++ = column_parity;
+ column_parity >>= 1;
+ }
+ *forward_ptr = 0;
+
+ return 45; //return number of emited bits
+}
+
+//====================================================================
+// Forward Link send function
+// Requires: forwarLink_data filled with valid bits (1 bit per byte)
+// fwd_bit_count set with number of bits to be sent
+//====================================================================
+void SendForward(uint8_t fwd_bit_count) {
+
+ fwd_write_ptr = forwardLink_data;
+ fwd_bit_sz = fwd_bit_count;
+
+ LED_D_ON();
+
+ //Field on
+ FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+
+ // Give it a bit of time for the resonant antenna to settle.
+ // And for the tag to fully power up
+ SpinDelay(150);
+
+ // force 1st mod pulse (start gap must be longer for 4305)
+ fwd_bit_sz--; //prepare next bit modulation
+ fwd_write_ptr++;
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
+ SpinDelayUs(55*8); //55 cycles off (8us each)for 4305
+ FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);//field on
+ SpinDelayUs(16*8); //16 cycles on (8us each)
+
+ // now start writting
+ while(fwd_bit_sz-- > 0) { //prepare next bit modulation
+ if(((*fwd_write_ptr++) & 1) == 1)
+ SpinDelayUs(32*8); //32 cycles at 125Khz (8us each)
+ else {
+ //These timings work for 4469/4269/4305 (with the 55*8 above)
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
+ SpinDelayUs(23*8); //16-4 cycles off (8us each)
+ FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);//field on
+ SpinDelayUs(9*8); //16 cycles on (8us each)
+ }
+ }
+}
+
+void Login (uint32_t Password) {
+
+ uint8_t fwd_bit_count;
+
+ forward_ptr = forwardLink_data;
+ fwd_bit_count = Prepare_Cmd( FWD_CMD_LOGIN );
+ fwd_bit_count += Prepare_Data( Password&0xFFFF, Password>>16 );
+
+ SendForward(fwd_bit_count);
+
+ //Wait for command to complete
+ SpinDelay(20);
+
+}
+
+void EM4xReadWord(uint8_t Address, uint32_t Pwd, uint8_t PwdMode) {
+
+ uint8_t fwd_bit_count;
+ uint8_t *dest = (uint8_t *)BigBuf;
+ int m=0, i=0;
+
+ //If password mode do login
+ if (PwdMode == 1) Login(Pwd);
+
+ forward_ptr = forwardLink_data;
+ fwd_bit_count = Prepare_Cmd( FWD_CMD_READ );
+ fwd_bit_count += Prepare_Addr( Address );
+
+ m = sizeof(BigBuf);
+ // Clear destination buffer before sending the command
+ memset(dest, 128, m);
+ // Connect the A/D to the peak-detected low-frequency path.
+ SetAdcMuxFor(GPIO_MUXSEL_LOPKD);
+ // Now set up the SSC to get the ADC samples that are now streaming at us.
+ FpgaSetupSsc();
+
+ SendForward(fwd_bit_count);
+
+ // Now do the acquisition
+ i = 0;
+ for(;;) {
+ if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
+ AT91C_BASE_SSC->SSC_THR = 0x43;
+ }
+ if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
+ dest[i] = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+ i++;
+ if (i >= m) break;
+ }
+ }
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
+ LED_D_OFF();
+}
+
+void EM4xWriteWord(uint32_t Data, uint8_t Address, uint32_t Pwd, uint8_t PwdMode) {
+
+ uint8_t fwd_bit_count;
+
+ //If password mode do login
+ if (PwdMode == 1) Login(Pwd);
+
+ forward_ptr = forwardLink_data;
+ fwd_bit_count = Prepare_Cmd( FWD_CMD_WRITE );
+ fwd_bit_count += Prepare_Addr( Address );
+ fwd_bit_count += Prepare_Data( Data&0xFFFF, Data>>16 );
+
+ SendForward(fwd_bit_count);
+
+ //Wait for write to complete
+ SpinDelay(20);
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); // field off
+ LED_D_OFF();
+}
+
projects / proxmark3-svn / commitdiff