[proxmark3-svn] / armsrc / pcf7931.c

#include "proxmark3.h"
#include "apps.h"
#include "lfsampling.h"
#include "pcf7931.h"
#include "util.h"
#include "string.h"

#define T0_PCF 8 //period for the pcf7931 in us
#define ALLOC 16

int DemodPCF7931(uint8_t **outBlocks) {

    uint8_t bits[256] = {0x00};
	uint8_t blocks[8][16];
    uint8_t *dest = BigBuf_get_addr();
    
	int GraphTraceLen = BigBuf_max_traceLen();
	if (  GraphTraceLen > 18000 )
		GraphTraceLen = 18000;
	
	
	int i, j, lastval, bitidx, half_switch;
	int clock = 64;
	int tolerance = clock / 8;
	int pmc, block_done;
	int lc, warnings = 0;
	int num_blocks = 0;
	int lmin=128, lmax=128;
	uint8_t dir;
	//clear read buffer
	BigBuf_Clear_keep_EM();

	LFSetupFPGAForADC(95, true);
	DoAcquisition_default(0, true);

	lmin = 64;
	lmax = 192;

	i = 2;

	/* Find first local max/min */
    if(dest[1] > dest[0]) {
		while(i < GraphTraceLen) {
            if( !(dest[i] > dest[i-1]) && dest[i] > lmax)
				break;
			i++;
		}
		dir = 0;
	}
	else {
		while(i < GraphTraceLen) {
            if( !(dest[i] < dest[i-1]) && dest[i] < lmin)
				break;
			i++;
		}
		dir = 1;
	}

	lastval = i++;
	half_switch = 0;
	pmc = 0;
	block_done = 0;

	for (bitidx = 0; i < GraphTraceLen; i++)
	{
        if ( (dest[i-1] > dest[i] && dir == 1 && dest[i] > lmax) || (dest[i-1] < dest[i] && dir == 0 && dest[i] < lmin))
		{
			lc = i - lastval;
			lastval = i;

			// Switch depending on lc length:
			// Tolerance is 1/8 of clock rate (arbitrary)
			if (ABS(lc-clock/4) < tolerance) {
				// 16T0
				if((i - pmc) == lc) { /* 16T0 was previous one */
					/* It's a PMC ! */
					i += (128+127+16+32+33+16)-1;
					lastval = i;
					pmc = 0;
					block_done = 1;
				}
				else {
					pmc = i;
				}
			} else if (ABS(lc-clock/2) < tolerance) {
				// 32TO
				if((i - pmc) == lc) { /* 16T0 was previous one */
					/* It's a PMC ! */
					i += (128+127+16+32+33)-1;
					lastval = i;
					pmc = 0;
					block_done = 1;
				}
				else if(half_switch == 1) {
                    bits[bitidx++] = 0;
					half_switch = 0;
				}
				else
					half_switch++;
			} else if (ABS(lc-clock) < tolerance) {
				// 64TO
                bits[bitidx++] = 1;
			} else {
				// Error
				warnings++;
				if (warnings > 10)
				{
					Dbprintf("Error: too many detection errors, aborting.");
					return 0;
				}
			}

			if(block_done == 1) {
				if(bitidx == 128) {
					for(j=0; j<16; j++) {
                        blocks[num_blocks][j] = 128*bits[j*8+7]+
                                64*bits[j*8+6]+
                                32*bits[j*8+5]+
                                16*bits[j*8+4]+
                                8*bits[j*8+3]+
                                4*bits[j*8+2]+
                                2*bits[j*8+1]+
                                bits[j*8];
						
					}
					num_blocks++;
				}
				bitidx = 0;
				block_done = 0;
				half_switch = 0;
			}
			if(i < GraphTraceLen)
                dir =(dest[i-1] > dest[i]) ? 0 : 1;
		}
		if(bitidx==255)
			bitidx=0;
		warnings = 0;
		if(num_blocks == 4) break;
	}
    memcpy(outBlocks, blocks, 16*num_blocks);
	return num_blocks;
}

int IsBlock0PCF7931(uint8_t *Block) {
	// Assume RFU means 0 :)
	if((memcmp(Block, "\x00\x00\x00\x00\x00\x00\x00\x01", 8) == 0) && memcmp(Block+9, "\x00\x00\x00\x00\x00\x00\x00", 7) == 0) // PAC enabled
		return 1;
	if((memcmp(Block+9, "\x00\x00\x00\x00\x00\x00\x00", 7) == 0) && Block[7] == 0) // PAC disabled, can it *really* happen ?
		return 1;
	return 0;
}

int IsBlock1PCF7931(uint8_t *Block) {
	// Assume RFU means 0 :)
	if(Block[10] == 0 && Block[11] == 0 && Block[12] == 0 && Block[13] == 0)
		if((Block[14] & 0x7f) <= 9 && Block[15] <= 9)
			return 1;

	return 0;
}

void ReadPCF7931() {
	uint8_t Blocks[8][17];
	uint8_t tmpBlocks[4][16];
	int i, j, ind, ind2, n;
	int num_blocks = 0;
	int max_blocks = 8;
	int ident = 0;
	int error = 0;
	int tries = 0;

	memset(Blocks, 0, 8*17*sizeof(uint8_t));

	do {
		memset(tmpBlocks, 0, 4*16*sizeof(uint8_t));
		n = DemodPCF7931((uint8_t**)tmpBlocks);
		if(!n)
			error++;
		if(error==10 && num_blocks == 0) {
			Dbprintf("Error, no tag or bad tag");
			return;
		}
		else if (tries==20 || error==10) {
			Dbprintf("Error reading the tag");
			Dbprintf("Here is the partial content");
			goto end;
		}

		for(i=0; i<n; i++)
			Dbprintf("(dbg) %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
					 tmpBlocks[i][0], tmpBlocks[i][1], tmpBlocks[i][2], tmpBlocks[i][3], tmpBlocks[i][4], tmpBlocks[i][5], tmpBlocks[i][6], tmpBlocks[i][7],
					tmpBlocks[i][8], tmpBlocks[i][9], tmpBlocks[i][10], tmpBlocks[i][11], tmpBlocks[i][12], tmpBlocks[i][13], tmpBlocks[i][14], tmpBlocks[i][15]);
		if(!ident) {
			for(i=0; i<n; i++) {
				if(IsBlock0PCF7931(tmpBlocks[i])) {
					// Found block 0 ?
					if(i < n-1 && IsBlock1PCF7931(tmpBlocks[i+1])) {
						// Found block 1!
						// \o/
						ident = 1;
						memcpy(Blocks[0], tmpBlocks[i], 16);
						Blocks[0][ALLOC] = 1;
						memcpy(Blocks[1], tmpBlocks[i+1], 16);
						Blocks[1][ALLOC] = 1;
						max_blocks = MAX((Blocks[1][14] & 0x7f), Blocks[1][15]) + 1;
						// Debug print
						Dbprintf("(dbg) Max blocks: %d", max_blocks);
						num_blocks = 2;
						// Handle following blocks
						for(j=i+2, ind2=2; j!=i; j++, ind2++, num_blocks++) {
							if(j==n) j=0;
							if(j==i) break;
							memcpy(Blocks[ind2], tmpBlocks[j], 16);
							Blocks[ind2][ALLOC] = 1;
						}
						break;
					}
				}
			}
		}
		else {
			for(i=0; i<n; i++) { // Look for identical block in known blocks
				if(memcmp(tmpBlocks[i], "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16)) { // Block is not full of 00
					for(j=0; j<max_blocks; j++) {
						if(Blocks[j][ALLOC] == 1 && !memcmp(tmpBlocks[i], Blocks[j], 16)) {
							// Found an identical block
							for(ind=i-1,ind2=j-1; ind >= 0; ind--,ind2--) {
								if(ind2 < 0)
									ind2 = max_blocks;
								if(!Blocks[ind2][ALLOC]) { // Block ind2 not already found
									// Dbprintf("Tmp %d -> Block %d", ind, ind2);
									memcpy(Blocks[ind2], tmpBlocks[ind], 16);
									Blocks[ind2][ALLOC] = 1;
									num_blocks++;
									if(num_blocks == max_blocks) goto end;
								}
							}
							for(ind=i+1,ind2=j+1; ind < n; ind++,ind2++) {
								if(ind2 > max_blocks)
									ind2 = 0;
								if(!Blocks[ind2][ALLOC]) { // Block ind2 not already found
									// Dbprintf("Tmp %d -> Block %d", ind, ind2);
									memcpy(Blocks[ind2], tmpBlocks[ind], 16);
									Blocks[ind2][ALLOC] = 1;
									num_blocks++;
									if(num_blocks == max_blocks) goto end;
								}
							}
						}
					}
				}
			}
		}
		tries++;
		if (BUTTON_PRESS()) return;
	} while (num_blocks != max_blocks);
 end:
	Dbprintf("-----------------------------------------");
	Dbprintf("Memory content:");
	Dbprintf("-----------------------------------------");
	for(i=0; i<max_blocks; i++) {
		if(Blocks[i][ALLOC]==1)
			Dbprintf("%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
					 Blocks[i][0], Blocks[i][1], Blocks[i][2], Blocks[i][3], Blocks[i][4], Blocks[i][5], Blocks[i][6], Blocks[i][7],
					Blocks[i][8], Blocks[i][9], Blocks[i][10], Blocks[i][11], Blocks[i][12], Blocks[i][13], Blocks[i][14], Blocks[i][15]);
		else
			Dbprintf("<missing block %d>", i);
	}
	Dbprintf("-----------------------------------------");

	cmd_send(CMD_ACK,0,0,0,0,0);
}


/* 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++)
	{
Commit	Line	Data
d10e08ae	1	#include "proxmark3.h"
	2	#include "apps.h"
	3	#include "lfsampling.h"
	4	#include "pcf7931.h"
b8e461ff	5	#include "util.h"
d10e08ae	6	#include "string.h"
	7
	8	#define T0_PCF 8 //period for the pcf7931 in us
	9	#define ALLOC 16
	10
d10e08ae	11	int DemodPCF7931(uint8_t **outBlocks) {
	12
	13	uint8_t bits[256] = {0x00};
	14	uint8_t blocks[8][16];
	15	uint8_t *dest = BigBuf_get_addr();
	16
	17	int GraphTraceLen = BigBuf_max_traceLen();
	18	if ( GraphTraceLen > 18000 )
	19	GraphTraceLen = 18000;
	20
	21
	22	int i, j, lastval, bitidx, half_switch;
	23	int clock = 64;
	24	int tolerance = clock / 8;
	25	int pmc, block_done;
	26	int lc, warnings = 0;
	27	int num_blocks = 0;
	28	int lmin=128, lmax=128;
	29	uint8_t dir;
3cec7061	30	//clear read buffer
29b75739	31	BigBuf_Clear_keep_EM();
d10e08ae	32
	33	LFSetupFPGAForADC(95, true);
	34	DoAcquisition_default(0, true);
	35
	36	lmin = 64;
	37	lmax = 192;
	38
	39	i = 2;
	40
	41	/* Find first local max/min */
	42	if(dest[1] > dest[0]) {
	43	while(i < GraphTraceLen) {
	44	if( !(dest[i] > dest[i-1]) && dest[i] > lmax)
	45	break;
	46	i++;
	47	}
	48	dir = 0;
	49	}
	50	else {
	51	while(i < GraphTraceLen) {
	52	if( !(dest[i] < dest[i-1]) && dest[i] < lmin)
	53	break;
	54	i++;
	55	}
	56	dir = 1;
	57	}
	58
	59	lastval = i++;
	60	half_switch = 0;
	61	pmc = 0;
	62	block_done = 0;
	63
	64	for (bitidx = 0; i < GraphTraceLen; i++)
	65	{
	66	if ( (dest[i-1] > dest[i] && dir == 1 && dest[i] > lmax) \|\| (dest[i-1] < dest[i] && dir == 0 && dest[i] < lmin))
	67	{
	68	lc = i - lastval;
	69	lastval = i;
	70
	71	// Switch depending on lc length:
	72	// Tolerance is 1/8 of clock rate (arbitrary)
cf194819	73	if (ABS(lc-clock/4) < tolerance) {
d10e08ae	74	// 16T0
	75	if((i - pmc) == lc) { /* 16T0 was previous one */
	76	/* It's a PMC ! */
	77	i += (128+127+16+32+33+16)-1;
	78	lastval = i;
	79	pmc = 0;
	80	block_done = 1;
	81	}
	82	else {
	83	pmc = i;
	84	}
cf194819	85	} else if (ABS(lc-clock/2) < tolerance) {
d10e08ae	86	// 32TO
	87	if((i - pmc) == lc) { /* 16T0 was previous one */
	88	/* It's a PMC ! */
	89	i += (128+127+16+32+33)-1;
	90	lastval = i;
	91	pmc = 0;
	92	block_done = 1;
	93	}
	94	else if(half_switch == 1) {
	95	bits[bitidx++] = 0;
	96	half_switch = 0;
	97	}
	98	else
	99	half_switch++;
cf194819	100	} else if (ABS(lc-clock) < tolerance) {
d10e08ae	101	// 64TO
	102	bits[bitidx++] = 1;
	103	} else {
	104	// Error
	105	warnings++;
	106	if (warnings > 10)
	107	{
	108	Dbprintf("Error: too many detection errors, aborting.");
	109	return 0;
	110	}
	111	}
	112
	113	if(block_done == 1) {
	114	if(bitidx == 128) {
	115	for(j=0; j<16; j++) {
	116	blocks[num_blocks][j] = 128bits[j8+7]+
	117	64bits[j8+6]+
	118	32bits[j8+5]+
	119	16bits[j8+4]+
	120	8bits[j8+3]+
	121	4bits[j8+2]+
	122	2bits[j8+1]+
	123	bits[j*8];
	124
	125	}
	126	num_blocks++;
	127	}
	128	bitidx = 0;
	129	block_done = 0;
	130	half_switch = 0;
	131	}
	132	if(i < GraphTraceLen)
	133	dir =(dest[i-1] > dest[i]) ? 0 : 1;
	134	}
	135	if(bitidx==255)
	136	bitidx=0;
	137	warnings = 0;
	138	if(num_blocks == 4) break;
	139	}
	140	memcpy(outBlocks, blocks, 16*num_blocks);
	141	return num_blocks;
	142	}
	143
	144	int IsBlock0PCF7931(uint8_t *Block) {
	145	// Assume RFU means 0 :)
	146	if((memcmp(Block, "\x00\x00\x00\x00\x00\x00\x00\x01", 8) == 0) && memcmp(Block+9, "\x00\x00\x00\x00\x00\x00\x00", 7) == 0) // PAC enabled
	147	return 1;
	148	if((memcmp(Block+9, "\x00\x00\x00\x00\x00\x00\x00", 7) == 0) && Block[7] == 0) // PAC disabled, can it really happen ?
	149	return 1;
	150	return 0;
	151	}
	152
	153	int IsBlock1PCF7931(uint8_t *Block) {
	154	// Assume RFU means 0 :)
	155	if(Block[10] == 0 && Block[11] == 0 && Block[12] == 0 && Block[13] == 0)
	156	if((Block[14] & 0x7f) <= 9 && Block[15] <= 9)
	157	return 1;
	158
	159	return 0;
	160	}
	161
	162	void ReadPCF7931() {
	163	uint8_t Blocks[8][17];
	164	uint8_t tmpBlocks[4][16];
165	int i, j, ind, ind2, n;
166	int num_blocks = 0;
167	int max_blocks = 8;
168	int ident = 0;
169	int error = 0;
170	int tries = 0;
171
172	memset(Blocks, 0, 817sizeof(uint8_t));
173
174	do {
175	memset(tmpBlocks, 0, 416sizeof(uint8_t));
176	n = DemodPCF7931((uint8_t**)tmpBlocks);
177	if(!n)
178	error++;
179	if(error==10 && num_blocks == 0) {
180	Dbprintf("Error, no tag or bad tag");
181	return;
182	}
183	else if (tries==20 \|\| error==10) {
184	Dbprintf("Error reading the tag");
185	Dbprintf("Here is the partial content");
186	goto end;
187	}
188
189	for(i=0; i<n; i++)
190	Dbprintf("(dbg) %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
191	tmpBlocks[i][0], tmpBlocks[i][1], tmpBlocks[i][2], tmpBlocks[i][3], tmpBlocks[i][4], tmpBlocks[i][5], tmpBlocks[i][6], tmpBlocks[i][7],
192	tmpBlocks[i][8], tmpBlocks[i][9], tmpBlocks[i][10], tmpBlocks[i][11], tmpBlocks[i][12], tmpBlocks[i][13], tmpBlocks[i][14], tmpBlocks[i][15]);
193	if(!ident) {
194	for(i=0; i<n; i++) {
195	if(IsBlock0PCF7931(tmpBlocks[i])) {
196	// Found block 0 ?
197	if(i < n-1 && IsBlock1PCF7931(tmpBlocks[i+1])) {
198	// Found block 1!
199	// \o/
200	ident = 1;
201	memcpy(Blocks[0], tmpBlocks[i], 16);
202	Blocks[0][ALLOC] = 1;
203	memcpy(Blocks[1], tmpBlocks[i+1], 16);
204	Blocks[1][ALLOC] = 1;
cf194819	205	max_blocks = MAX((Blocks[1][14] & 0x7f), Blocks[1][15]) + 1;
d10e08ae	206	// Debug print
	207	Dbprintf("(dbg) Max blocks: %d", max_blocks);
	208	num_blocks = 2;
	209	// Handle following blocks
	210	for(j=i+2, ind2=2; j!=i; j++, ind2++, num_blocks++) {
	211	if(j==n) j=0;
	212	if(j==i) break;
	213	memcpy(Blocks[ind2], tmpBlocks[j], 16);
	214	Blocks[ind2][ALLOC] = 1;
	215	}
	216	break;
	217	}
	218	}
	219	}
	220	}
	221	else {
	222	for(i=0; i<n; i++) { // Look for identical block in known blocks
	223	if(memcmp(tmpBlocks[i], "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16)) { // Block is not full of 00
	224	for(j=0; j<max_blocks; j++) {
	225	if(Blocks[j][ALLOC] == 1 && !memcmp(tmpBlocks[i], Blocks[j], 16)) {
	226	// Found an identical block
	227	for(ind=i-1,ind2=j-1; ind >= 0; ind--,ind2--) {
	228	if(ind2 < 0)
	229	ind2 = max_blocks;
	230	if(!Blocks[ind2][ALLOC]) { // Block ind2 not already found
	231	// Dbprintf("Tmp %d -> Block %d", ind, ind2);
	232	memcpy(Blocks[ind2], tmpBlocks[ind], 16);
	233	Blocks[ind2][ALLOC] = 1;
	234	num_blocks++;
	235	if(num_blocks == max_blocks) goto end;
	236	}
	237	}
	238	for(ind=i+1,ind2=j+1; ind < n; ind++,ind2++) {
	239	if(ind2 > max_blocks)
	240	ind2 = 0;
	241	if(!Blocks[ind2][ALLOC]) { // Block ind2 not already found
	242	// Dbprintf("Tmp %d -> Block %d", ind, ind2);
	243	memcpy(Blocks[ind2], tmpBlocks[ind], 16);
	244	Blocks[ind2][ALLOC] = 1;
	245	num_blocks++;
	246	if(num_blocks == max_blocks) goto end;
	247	}
	248	}
	249	}
	250	}
	251	}
	252	}
	253	}
	254	tries++;
	255	if (BUTTON_PRESS()) return;
	256	} while (num_blocks != max_blocks);
	257	end:
	258	Dbprintf("-----------------------------------------");
	259	Dbprintf("Memory content:");
	260	Dbprintf("-----------------------------------------");
	261	for(i=0; i<max_blocks; i++) {
	262	if(Blocks[i][ALLOC]==1)
	263	Dbprintf("%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
	264	Blocks[i][0], Blocks[i][1], Blocks[i][2], Blocks[i][3], Blocks[i][4], Blocks[i][5], Blocks[i][6], Blocks[i][7],
	265	Blocks[i][8], Blocks[i][9], Blocks[i][10], Blocks[i][11], Blocks[i][12], Blocks[i][13], Blocks[i][14], Blocks[i][15]);
	266	else
	267	Dbprintf("<missing block %d>", i);
	268	}
	269	Dbprintf("-----------------------------------------");
270
7cfc777b	271	cmd_send(CMD_ACK,0,0,0,0,0);
d10e08ae	272	}
	273
	274
	275	/* Write on a byte of a PCF7931 tag
	276	* @param address : address of the block to write
	277	@param byte : address of the byte to write
	278	@param data : data to write
	279	*/
	280	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)
	281	{
	282
	283	uint32_t tab[1024]={0}; // data times frame
	284	uint32_t u = 0;
	285	uint8_t parity = 0;
	286	bool comp = 0;
	287
	288	//BUILD OF THE DATA FRAME
	289
	290	//alimentation of the tag (time for initializing)
	291	AddPatternPCF7931(init_delay, 0, 8192/2*T0_PCF, tab);
	292
	293	//PMC
	294	Dbprintf("Initialization delay : %d us", init_delay);
	295	AddPatternPCF7931(8192/2T0_PCF + 319T0_PCF+70, 3T0_PCF, 29T0_PCF, tab);
	296
	297	Dbprintf("Offsets : %d us on the low pulses width, %d us on the low pulses positions", l, p);
	298
	299	//password indication bit
	300	AddBitPCF7931(1, tab, l, p);
	301
	302
	303	//password (on 56 bits)
	304	Dbprintf("Password (LSB first on each byte) : %02x %02x %02x %02x %02x %02x %02x", pass1,pass2,pass3,pass4,pass5,pass6,pass7);
	305	AddBytePCF7931(pass1, tab, l, p);
	306	AddBytePCF7931(pass2, tab, l, p);
	307	AddBytePCF7931(pass3, tab, l, p);
	308	AddBytePCF7931(pass4, tab, l, p);
	309	AddBytePCF7931(pass5, tab, l, p);
	310	AddBytePCF7931(pass6, tab, l, p);
	311	AddBytePCF7931(pass7, tab, l, p);
	312
	313	//programming mode (0 or 1)
	314	AddBitPCF7931(0, tab, l, p);
	315
	316	//block adress on 6 bits
	317	Dbprintf("Block address : %02x", address);
	318	for (u=0; u<6; u++)
	319	{
	320	if (address&(1<<u)) { // bit 1
	321	parity++;
	322	AddBitPCF7931(1, tab, l, p);
	323	} else{ // bit 0
	324	AddBitPCF7931(0, tab, l, p);
	325	}
	326	}
	327
	328	//byte address on 4 bits
	329	Dbprintf("Byte address : %02x", byte);
	330	for (u=0; u<4; u++)
	331	{
	332	if (byte&(1<<u)) { // bit 1
	333	parity++;
	334	AddBitPCF7931(1, tab, l, p);
	335	} else{ // bit 0
336	AddBitPCF7931(0, tab, l, p);
337	}
338	}
339
340	//data on 8 bits
341	Dbprintf("Data : %02x", data);
342	for (u=0; u<8; u++)
343	{
344	if (data&(1<<u)) { // bit 1
345	parity++;
346	AddBitPCF7931(1, tab, l, p);
347	} else{ //bit 0
348	AddBitPCF7931(0, tab, l, p);
349	}
350	}
351
352
353	//parity bit
354	if((parity%2)==0){
355	AddBitPCF7931(0, tab, l, p); //even parity
356	}else{
357	AddBitPCF7931(1, tab, l, p);//odd parity
358	}
359
360	//time access memory
361	AddPatternPCF7931(5120+2680, 0, 0, tab);
362
363	//conversion of the scale time
364	for(u=0;u<500;u++){
365	tab[u]=(tab[u] * 3)/2;
366	}
367
368
369	//compennsation of the counter reload
370	while (!comp){
371	comp = 1;
372	for(u=0;tab[u]!=0;u++){
373	if(tab[u] > 0xFFFF){
374	tab[u] -= 0xFFFF;
375	comp = 0;
376	}
377	}
378	}
379
380	SendCmdPCF7931(tab);
381	}
382
383
384
385	/* Send a trame to a PCF7931 tags
386	* @param tab : array of the data frame
387	*/
388
389	void SendCmdPCF7931(uint32_t * tab){
390	uint16_t u=0;
391	uint16_t tempo=0;
392
393	Dbprintf("SENDING DATA FRAME...");
394
395	FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
396
397	FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
398
399	FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_PASSTHRU );
400
401	LED_A_ON();
402
403	// steal this pin from the SSP and use it to control the modulation
404	AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DOUT;
405	AT91C_BASE_PIOA->PIO_OER = GPIO_SSC_DOUT;
406
407	//initialization of the timer
408	AT91C_BASE_PMC->PMC_PCER \|= (0x1 << 12) \| (0x1 << 13) \| (0x1 << 14);
409	AT91C_BASE_TCB->TCB_BMR = AT91C_TCB_TC0XC0S_NONE \| AT91C_TCB_TC1XC1S_TIOA0 \| AT91C_TCB_TC2XC2S_NONE;
410	AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // timer disable
411	AT91C_BASE_TC0->TC_CMR = AT91C_TC_CLKS_TIMER_DIV3_CLOCK; //clock at 48/32 MHz
412	AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKEN;
413	AT91C_BASE_TCB->TCB_BCR = 1;
414
415
416	tempo = AT91C_BASE_TC0->TC_CV;
417	for(u=0;tab[u]!= 0;u+=3){
418
419
420	// modulate antenna
421	HIGH(GPIO_SSC_DOUT);
422	while(tempo != tab[u]){
423	tempo = AT91C_BASE_TC0->TC_CV;
424	}
425
426	// stop modulating antenna
427	LOW(GPIO_SSC_DOUT);
428	while(tempo != tab[u+1]){
429	tempo = AT91C_BASE_TC0->TC_CV;
430	}
431
432
433	// modulate antenna
434	HIGH(GPIO_SSC_DOUT);
435	while(tempo != tab[u+2]){
436	tempo = AT91C_BASE_TC0->TC_CV;
437	}
438
439
440	}
441
442	LED_A_OFF();
443	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
444	SpinDelay(200);
445
446
447	AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS; // timer disable
448	DbpString("FINISH !");
449	DbpString("(Could be usefull to send the same trame many times)");
450	LED(0xFFFF, 1000);
451	}
452
453
454	/* Add a byte for building the data frame of PCF7931 tags
455	* @param b : byte to add
456	* @param tab : array of the data frame
457	* @param l : offset on low pulse width
458	* @param p : offset on low pulse positioning
459	*/
460
461	bool AddBytePCF7931(uint8_t byte, uint32_t * tab, int32_t l, int32_t p){
462
463	uint32_t u;
464	for (u=0; u<8; u++)
465	{
466