+
+
+#define T0_PCF 8 //period for the pcf7931 in us
+
+/* Write on a byte of a PCF7931 tag
+ * @param address : address of the block to write
+ @param byte : address of the byte to write
+ @param data : data to write
+ */
+void WritePCF7931(uint8_t pass1, uint8_t pass2, uint8_t pass3, uint8_t pass4, uint8_t pass5, uint8_t pass6, uint8_t pass7, uint16_t init_delay, int32_t l, int32_t p, uint8_t address, uint8_t byte, uint8_t data)
+{
+
+ uint32_t tab[1024]={0}; // data times frame
+ uint32_t u = 0;
+ uint8_t parity = 0;
+ bool comp = 0;
+
+
+ //BUILD OF THE DATA FRAME
+
+ //alimentation of the tag (time for initializing)
+ AddPatternPCF7931(init_delay, 0, 8192/2*T0_PCF, tab);
+
+ //PMC
+ Dbprintf("Initialization delay : %d us", init_delay);
+ AddPatternPCF7931(8192/2*T0_PCF + 319*T0_PCF+70, 3*T0_PCF, 29*T0_PCF, tab);
+
+ Dbprintf("Offsets : %d us on the low pulses width, %d us on the low pulses positions", l, p);
+
+ //password indication bit
+ AddBitPCF7931(1, tab, l, p);
+
+
+ //password (on 56 bits)
+ Dbprintf("Password (LSB first on each byte) : %02x %02x %02x %02x %02x %02x %02x", pass1,pass2,pass3,pass4,pass5,pass6,pass7);
+ AddBytePCF7931(pass1, tab, l, p);
+ AddBytePCF7931(pass2, tab, l, p);
+ AddBytePCF7931(pass3, tab, l, p);
+ AddBytePCF7931(pass4, tab, l, p);
+ AddBytePCF7931(pass5, tab, l, p);
+ AddBytePCF7931(pass6, tab, l, p);
+ AddBytePCF7931(pass7, tab, l, p);
+
+
+ //programming mode (0 or 1)
+ AddBitPCF7931(0, tab, l, p);
+
+ //block adress on 6 bits
+ Dbprintf("Block address : %02x", address);
+ for (u=0; u<6; u++)
+ {
+ if (address&(1<<u)) { // bit 1
+ parity++;
+ AddBitPCF7931(1, tab, l, p);
+ } else{ // bit 0
+ AddBitPCF7931(0, tab, l, p);
+ }
+ }
+
+ //byte address on 4 bits
+ Dbprintf("Byte address : %02x", byte);
+ for (u=0; u<4; u++)
+ {
+ if (byte&(1<<u)) { // bit 1
+ parity++;
+ AddBitPCF7931(1, tab, l, p);
+ } else{ // bit 0
+ AddBitPCF7931(0, tab, l, p);
+ }
+ }
+
+ //data on 8 bits
+ Dbprintf("Data : %02x", data);
+ for (u=0; u<8; u++)
+ {
+ if (data&(1<<u)) { // bit 1
+ parity++;
+ AddBitPCF7931(1, tab, l, p);
+ } else{ //bit 0
+ AddBitPCF7931(0, tab, l, p);
+ }
+ }
+
+
+ //parity bit
+ if((parity%2)==0){
+ AddBitPCF7931(0, tab, l, p); //even parity
+ }else{
+ AddBitPCF7931(1, tab, l, p);//odd parity
+ }
+
+ //time access memory
+ AddPatternPCF7931(5120+2680, 0, 0, tab);
+
+ //conversion of the scale time
+ for(u=0;u<500;u++){
+ tab[u]=(tab[u] * 3)/2;
+ }
+
+
+ //compennsation of the counter reload
+ while (!comp){
+ comp = 1;
+ for(u=0;tab[u]!=0;u++){
+ if(tab[u] > 0xFFFF){
+ tab[u] -= 0xFFFF;
+ comp = 0;
+ }
+ }
+ }
+
+ SendCmdPCF7931(tab);
+}
+
+
+
+/* Send a trame to a PCF7931 tags
+ * @param tab : array of the data frame
+ */
+
+void SendCmdPCF7931(uint32_t * tab){
+ uint16_t u=0;
+ uint16_t tempo=0;
+
+ Dbprintf("SENDING DATA FRAME...");
+
+ FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
+
+ FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
+
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_PASSTHRU );
+
+ LED_A_ON();
+
+ // steal this pin from the SSP and use it to control the modulation
+ AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DOUT;
+ AT91C_BASE_PIOA->PIO_OER = GPIO_SSC_DOUT;
+
+ //initialization of the timer
+ AT91C_BASE_PMC->PMC_PCER |= (0x1 << 12) | (0x1 << 13) | (0x1 << 14);
+ AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_NONE | AT91C_TCB_TC1XC1S_TIOA0 | AT91C_TCB_TC2XC2S_NONE;
+ AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // timer disable
+ AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_TIMER_DIV3_CLOCK; //clock at 48/32 MHz
+ AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN;
+ AT91C_BASE_TCB->TCB_BCR = 1;
+
+
+ tempo = AT91C_BASE_TC0->TC_CV;
+ for(u=0;tab[u]!= 0;u+=3){
+
+
+ // modulate antenna
+ HIGH(GPIO_SSC_DOUT);
+ while(tempo != tab[u]){
+ tempo = AT91C_BASE_TC0->TC_CV;
+ }
+
+ // stop modulating antenna
+ LOW(GPIO_SSC_DOUT);
+ while(tempo != tab[u+1]){
+ tempo = AT91C_BASE_TC0->TC_CV;
+ }
+
+
+ // modulate antenna
+ HIGH(GPIO_SSC_DOUT);
+ while(tempo != tab[u+2]){
+ tempo = AT91C_BASE_TC0->TC_CV;
+ }
+
+
+ }
+
+ LED_A_OFF();
+ FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+ SpinDelay(200);
+
+
+ AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // timer disable
+ DbpString("FINISH !");
+ DbpString("(Could be usefull to send the same trame many times)");
+ LED(0xFFFF, 1000);
+}
+
+
+/* Add a byte for building the data frame of PCF7931 tags
+ * @param b : byte to add
+ * @param tab : array of the data frame
+ * @param l : offset on low pulse width
+ * @param p : offset on low pulse positioning
+ */
+
+bool AddBytePCF7931(uint8_t byte, uint32_t * tab, int32_t l, int32_t p){
+
+ uint32_t u;
+ for (u=0; u<8; u++)
+ {
+ if (byte&(1<<u)) { //bit à 1
+ if(AddBitPCF7931(1, tab, l, p)==1)return 1;
+ } else { //bit à 0
+ if(AddBitPCF7931(0, tab, l, p)==1)return 1;
+ }
+ }
+
+ return 0;
+}
+
+/* Add a bits for building the data frame of PCF7931 tags
+ * @param b : bit to add
+ * @param tab : array of the data frame
+ * @param l : offset on low pulse width
+ * @param p : offset on low pulse positioning
+ */
+bool AddBitPCF7931(bool b, uint32_t * tab, int32_t l, int32_t p){
+ uint8_t u = 0;
+
+ for(u=0;tab[u]!=0;u+=3){} //we put the cursor at the last value of the array
+
+
+ if(b==1){ //add a bit 1
+ if(u==0) tab[u] = 34*T0_PCF+p;
+ else tab[u] = 34*T0_PCF+tab[u-1]+p;
+
+ tab[u+1] = 6*T0_PCF+tab[u]+l;
+ tab[u+2] = 88*T0_PCF+tab[u+1]-l-p;
+ return 0;
+ }else{ //add a bit 0
+
+ if(u==0) tab[u] = 98*T0_PCF+p;
+ else tab[u] = 98*T0_PCF+tab[u-1]+p;
+
+ tab[u+1] = 6*T0_PCF+tab[u]+l;
+ tab[u+2] = 24*T0_PCF+tab[u+1]-l-p;
+ return 0;
+ }
+
+
+ return 1;
+}
+
+/* Add a custom pattern in the data frame
+ * @param a : delay of the first high pulse
+ * @param b : delay of the low pulse
+ * @param c : delay of the last high pulse
+ * @param tab : array of the data frame
+ */
+bool AddPatternPCF7931(uint32_t a, uint32_t b, uint32_t c, uint32_t * tab){
+ uint32_t u = 0;
+ for(u=0;tab[u]!=0;u+=3){} //we put the cursor at the last value of the array
+
+ if(u==0) tab[u] = a;
+ else tab[u] = a + tab[u-1];
+
+ tab[u+1] = b+tab[u];
+ tab[u+2] = c+tab[u+1];
+
+ return 0;
+}
\ No newline at end of file
projects / proxmark3-svn / blobdiff