X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/b8d34d0598d48ed365053acc2830f1b883c732a0..f218d50efb324da7f268d9b657a5be93d702c4f8:/armsrc/iso14443b.c

diff --git a/armsrc/iso14443b.c b/armsrc/iso14443b.c
index 416c31f9..0b9962e1 100644
--- a/armsrc/iso14443b.c
+++ b/armsrc/iso14443b.c
@@ -13,12 +13,15 @@
 #include "apps.h"
 #include "util.h"
 #include "string.h"
-
 #include "iso14443crc.h"
-
-#define RECEIVE_SAMPLES_TIMEOUT 2000
+#include "common.h"
+#define RECEIVE_SAMPLES_TIMEOUT 600000
 #define ISO14443B_DMA_BUFFER_SIZE 256
 
+
+// PCB Block number for APDUs
+static uint8_t pcb_blocknum = 0;
+
 //=============================================================================
 // An ISO 14443 Type B tag. We listen for commands from the reader, using
 // a UART kind of thing that's implemented in software. When we get a
@@ -240,7 +243,7 @@ static RAMFUNC int Handle14443bUartBit(uint8_t bit)
 					LED_A_OFF(); // Finished receiving
 					Uart.state = STATE_UNSYNCD;
 					if (Uart.byteCnt != 0) {
-						return TRUE;
+					return TRUE;
 					}
 				} else {
 					// this is an error
@@ -266,6 +269,8 @@ static void UartReset()
 	Uart.state = STATE_UNSYNCD;
 	Uart.byteCnt = 0;
 	Uart.bitCnt = 0;
+	Uart.posCnt = 0;
+	memset(Uart.output, 0x00, MAX_FRAME_SIZE);
 }
 
 
@@ -321,10 +326,14 @@ static int GetIso14443bCommandFromReader(uint8_t *received, uint16_t *len)
 //-----------------------------------------------------------------------------
 void SimulateIso14443bTag(void)
 {
-	// the only commands we understand is REQB, AFI=0, Select All, N=0:
-	static const uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 };
-	// ... and REQB, AFI=0, Normal Request, N=0:
-	static const uint8_t cmd2[] = { 0x05, 0x00, 0x00, 0x71, 0xFF };
+	// the only commands we understand is WUPB, AFI=0, Select All, N=1:
+	static const uint8_t cmd1[] = { 0x05, 0x00, 0x08, 0x39, 0x73 }; // WUPB
+	// ... and REQB, AFI=0, Normal Request, N=1:
+	static const uint8_t cmd2[] = { 0x05, 0x00, 0x00, 0x71, 0xFF }; // REQB
+	// ... and HLTB
+	static const uint8_t cmd3[] = { 0x50, 0xff, 0xff, 0xff, 0xff }; // HLTB
+	// ... and ATTRIB
+	static const uint8_t cmd4[] = { 0x1D, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; // ATTRIB
 
 	// ... and we always respond with ATQB, PUPI = 820de174, Application Data = 0x20381922,
 	// supports only 106kBit/s in both directions, max frame size = 32Bytes,
@@ -333,6 +342,12 @@ void SimulateIso14443bTag(void)
 		0x50, 0x82, 0x0d, 0xe1, 0x74, 0x20, 0x38, 0x19, 0x22,
 		0x00, 0x21, 0x85, 0x5e, 0xd7
 	};
+	// response to HLTB and ATTRIB
+	static const uint8_t response2[] = {0x00, 0x78, 0xF0};
+
+	uint8_t parity[MAX_PARITY_SIZE];
+				
+	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
 
 	clear_trace();
 	set_tracing(TRUE);
@@ -348,14 +363,18 @@ void SimulateIso14443bTag(void)
 	uint16_t len;
 	uint16_t cmdsRecvd = 0;
 
-	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-
 	// prepare the (only one) tag answer:
 	CodeIso14443bAsTag(response1, sizeof(response1));
 	uint8_t *resp1Code = BigBuf_malloc(ToSendMax);
 	memcpy(resp1Code, ToSend, ToSendMax); 
 	uint16_t resp1CodeLen = ToSendMax;
 
+	// prepare the (other) tag answer:
+	CodeIso14443bAsTag(response2, sizeof(response2));
+	uint8_t *resp2Code = BigBuf_malloc(ToSendMax);
+	memcpy(resp2Code, ToSend, ToSendMax); 
+	uint16_t resp2CodeLen = ToSendMax;
+
 	// We need to listen to the high-frequency, peak-detected path.
 	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
 	FpgaSetupSsc();
@@ -365,12 +384,11 @@ void SimulateIso14443bTag(void)
 	for(;;) {
 
 		if(!GetIso14443bCommandFromReader(receivedCmd, &len)) {
-			Dbprintf("button pressed, received %d commands", cmdsRecvd);
-			break;
+		Dbprintf("button pressed, received %d commands", cmdsRecvd);
+		break;
 		}
 
 		if (tracing) {
-			uint8_t parity[MAX_PARITY_SIZE];
 			LogTrace(receivedCmd, len, 0, 0, parity, TRUE);
 		}
 
@@ -381,18 +399,33 @@ void SimulateIso14443bTag(void)
 			respLen = sizeof(response1);
 			respCode = resp1Code; 
 			respCodeLen = resp1CodeLen;
+		} else if ( (len == sizeof(cmd3) && receivedCmd[0] == cmd3[0])
+			|| (len == sizeof(cmd4) && receivedCmd[0] == cmd4[0]) ) {
+			resp = response2; 
+			respLen = sizeof(response2);
+			respCode = resp2Code; 
+			respCodeLen = resp2CodeLen;
 		} else {
 			Dbprintf("new cmd from reader: len=%d, cmdsRecvd=%d", len, cmdsRecvd);
 			// And print whether the CRC fails, just for good measure
 			uint8_t b1, b2;
+			if (len >= 3){ // if crc exists
 			ComputeCrc14443(CRC_14443_B, receivedCmd, len-2, &b1, &b2);
 			if(b1 != receivedCmd[len-2] || b2 != receivedCmd[len-1]) {
 				// Not so good, try again.
 				DbpString("+++CRC fail");
+		
 			} else {
 				DbpString("CRC passes");
 			}
-			break;
+			}
+			//get rid of compiler warning
+			respCodeLen = 0;
+			resp = response1;
+			respLen	= 0;
+			respCode = resp1Code;
+			//don't crash at new command just wait and see if reader will send other new cmds.
+			//break;
 		}
 
 		cmdsRecvd++;
@@ -411,32 +444,42 @@ void SimulateIso14443bTag(void)
 		AT91C_BASE_SSC->SSC_THR = 0xff;
 		FpgaSetupSsc();
 
+		uint8_t c;
+	 	// clear receiving shift register and holding register
+		while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));
+		c = AT91C_BASE_SSC->SSC_RHR; (void) c;
+		while(!(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY));
+		c = AT91C_BASE_SSC->SSC_RHR; (void) c;
+		
+		// Clear TXRDY:
+		AT91C_BASE_SSC->SSC_THR = 0x00;
+		
 		// Transmit the response.
+		uint16_t FpgaSendQueueDelay = 0;
 		uint16_t i = 0;
-		for(;;) {
+		for(;i < respCodeLen; ) {
 			if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
-				uint8_t b = respCode[i];
-
-				AT91C_BASE_SSC->SSC_THR = b;
-
-				i++;
-				if(i > respCodeLen) {
-					break;
-				}
+				AT91C_BASE_SSC->SSC_THR = respCode[i++];
+				FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
 			}
-			if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-				volatile uint8_t b = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
-				(void)b;
+				if(BUTTON_PRESS()) break;
+		}
+		
+		// Ensure that the FPGA Delay Queue is empty before we switch to TAGSIM_LISTEN again:
+		uint8_t fpga_queued_bits = FpgaSendQueueDelay >> 3;
+		for (i = 0; i <= fpga_queued_bits/8 + 1; ) {
+			if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
+				AT91C_BASE_SSC->SSC_THR = 0x00;
+				FpgaSendQueueDelay = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
+				i++;
 			}
 		}
 		
 		// trace the response:
-		if (tracing) {
-			uint8_t parity[MAX_PARITY_SIZE];
-			LogTrace(resp, respLen, 0, 0, parity, FALSE);
-		}
-			
+		if (tracing) LogTrace(resp, respLen, 0, 0, parity, FALSE);			
 	}
+	FpgaDisableSscDma();
+	set_tracing(FALSE);	
 }
 
 //=============================================================================
@@ -483,9 +526,14 @@ static struct {
  *          false if we are still waiting for some more
  *
  */
+ #define abs(x) ( ((x)<0) ? -(x) : (x) )
 static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 {
-	int v;
+	int v = 0;
+	int ai = abs(ci);
+	int aq = abs(cq);
+	int halfci = (ai >> 1);
+	int halfcq = (aq >> 1);
 
 // The soft decision on the bit uses an estimate of just the
 // quadrant of the reference angle, not the exact angle.
@@ -504,50 +552,12 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 
 #define SUBCARRIER_DETECT_THRESHOLD	8
 
-// Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by abs(ci) + abs(cq)
-/* #define CHECK_FOR_SUBCARRIER() { \
-		v = ci; \
-		if(v < 0) v = -v; \
-		if(cq > 0) { \
-			v += cq; \
-		} else { \
-			v -= cq; \
-		} \
-	}		
- */
 // Subcarrier amplitude v = sqrt(ci^2 + cq^2), approximated here by max(abs(ci),abs(cq)) + 1/2*min(abs(ci),abs(cq)))
 #define CHECK_FOR_SUBCARRIER() { \
-		if(ci < 0) { \
-			if(cq < 0) { /* ci < 0, cq < 0 */ \
-				if (cq < ci) { \
-					v = -cq - (ci >> 1); \
-				} else { \
-					v = -ci - (cq >> 1); \
-				} \
-			} else {	/* ci < 0, cq >= 0 */ \
-				if (cq < -ci) { \
-					v = -ci + (cq >> 1); \
-				} else { \
-					v = cq - (ci >> 1); \
-				} \
-			} \
-		} else { \
-			if(cq < 0) { /* ci >= 0, cq < 0 */ \
-				if (-cq < ci) { \
-					v = ci - (cq >> 1); \
-				} else { \
-					v = -cq + (ci >> 1); \
-				} \
-			} else {	/* ci >= 0, cq >= 0 */ \
-				if (cq < ci) { \
-					v = ci + (cq >> 1); \
-				} else { \
-					v = cq + (ci >> 1); \
-				} \
-			} \
-		} \
-	}
-	
+		v = MAX(ai, aq) + MIN(halfci, halfcq); \
+}
+
+
 	switch(Demod.state) {
 		case DEMOD_UNSYNCD:
 			CHECK_FOR_SUBCARRIER();
@@ -556,11 +566,12 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 				Demod.sumI = ci;
 				Demod.sumQ = cq;
 				Demod.posCount = 1;
-				}
+			}
 			break;
 
 		case DEMOD_PHASE_REF_TRAINING:
 			if(Demod.posCount < 8) {
+			//if(Demod.posCount < 10*2) {
 				CHECK_FOR_SUBCARRIER();
 				if (v > SUBCARRIER_DETECT_THRESHOLD) {
 					// set the reference phase (will code a logic '1') by averaging over 32 1/fs.
@@ -578,11 +589,12 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 
 		case DEMOD_AWAITING_FALLING_EDGE_OF_SOF:
 			MAKE_SOFT_DECISION();
-			if(v < 0) {	// logic '0' detected
+			//Dbprintf("ICE: %d %d %d %d %d", v, Demod.sumI, Demod.sumQ, ci, cq );
+			if(v <= 0) {	// logic '0' detected
 				Demod.state = DEMOD_GOT_FALLING_EDGE_OF_SOF;
 				Demod.posCount = 0;	// start of SOF sequence
 			} else {
-				if(Demod.posCount > 200/4) {	// maximum length of TR1 = 200 1/fs
+				if(Demod.posCount > 25*2) {	// maximum length of TR1 = 200 1/fs
 					Demod.state = DEMOD_UNSYNCD;
 				}
 			}
@@ -593,7 +605,7 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 			Demod.posCount++;
 			MAKE_SOFT_DECISION();
 			if(v > 0) {
-				if(Demod.posCount < 9*2) { // low phase of SOF too short (< 9 etu). Note: spec is >= 10, but FPGA tends to "smear" edges
+				if(Demod.posCount < 10*2) { // low phase of SOF too short (< 9 etu). Note: spec is >= 10, but FPGA tends to "smear" edges
 					Demod.state = DEMOD_UNSYNCD;
 				} else {
 					LED_C_ON(); // Got SOF
@@ -606,7 +618,7 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 */
 				}
 			} else {
-				if(Demod.posCount > 12*2) { // low phase of SOF too long (> 12 etu)
+				if(Demod.posCount > 13*2) { // low phase of SOF too long (> 12 etu)
 					Demod.state = DEMOD_UNSYNCD;
 					LED_C_OFF();
 				}
@@ -678,7 +690,6 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq)
 			LED_C_OFF();
 			break;
 	}
-
 	return FALSE;
 }
 
@@ -689,6 +700,11 @@ static void DemodReset()
 	Demod.len = 0;
 	Demod.state = DEMOD_UNSYNCD;
 	Demod.posCount = 0;
+	Demod.sumI = 0;
+	Demod.sumQ = 0;
+	Demod.bitCount = 0;
+	Demod.thisBit = 0;
+	Demod.shiftReg = 0;
 	memset(Demod.output, 0x00, MAX_FRAME_SIZE);
 }
 
@@ -713,27 +729,25 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
 	// Allocate memory from BigBuf for some buffers
 	// free all previous allocations first
 	BigBuf_free();
-	
+
+	// And put the FPGA in the appropriate mode
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
+
 	// The response (tag -> reader) that we're receiving.
-	uint8_t *receivedResponse = BigBuf_malloc(MAX_FRAME_SIZE);
+	// Set up the demodulator for tag -> reader responses.
+	DemodInit(BigBuf_malloc(MAX_FRAME_SIZE));
 	
 	// The DMA buffer, used to stream samples from the FPGA
 	int8_t *dmaBuf = (int8_t*) BigBuf_malloc(ISO14443B_DMA_BUFFER_SIZE);
 
-	// Set up the demodulator for tag -> reader responses.
-	DemodInit(receivedResponse);
-
 	// Setup and start DMA.
 	FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE);
-
+	
 	int8_t *upTo = dmaBuf;
 	lastRxCounter = ISO14443B_DMA_BUFFER_SIZE;
 
 	// Signal field is ON with the appropriate LED:
 	LED_D_ON();
-	// And put the FPGA in the appropriate mode
-	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
-
 	for(;;) {
 		int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR;
 		if(behindBy > max) max = behindBy;
@@ -749,15 +763,15 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
 			}
 			lastRxCounter -= 2;
 			if(lastRxCounter <= 0) {
-				lastRxCounter += ISO14443B_DMA_BUFFER_SIZE;
+				lastRxCounter = ISO14443B_DMA_BUFFER_SIZE;
 			}
 
 			samples += 2;
 
-			if(Handle14443bSamplesDemod(ci, cq)) {
-				gotFrame = TRUE;
+			//
+			gotFrame = Handle14443bSamplesDemod(ci , cq );
+			if ( gotFrame )
 				break;
-			}
 		}
 
 		if(samples > n || gotFrame) {
@@ -767,7 +781,17 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
 
 	AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
 
-	if (!quiet) Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Demod.len = %d, Demod.sumI = %d, Demod.sumQ = %d", max, samples, gotFrame, Demod.len, Demod.sumI, Demod.sumQ);
+	if (!quiet && Demod.len == 0) {
+		Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Demod.len = %d, Demod.sumI = %d, Demod.sumQ = %d",
+			max,
+			samples, 
+			gotFrame, 
+			Demod.len, 
+			Demod.sumI, 
+			Demod.sumQ
+		);
+	}
+
 	//Tracing
 	if (tracing && Demod.len > 0) {
 		uint8_t parity[MAX_PARITY_SIZE];
@@ -784,7 +808,7 @@ static void TransmitFor14443b(void)
 	int c;
 
 	FpgaSetupSsc();
-
+	
 	while(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
 		AT91C_BASE_SSC->SSC_THR = 0xff;
 	}
@@ -794,7 +818,7 @@ static void TransmitFor14443b(void)
 	// Signal we are transmitting with the Green LED
 	LED_B_ON();
 	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
-
+	
 	for(c = 0; c < 10;) {
 		if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_TXRDY)) {
 			AT91C_BASE_SSC->SSC_THR = 0xff;
@@ -842,7 +866,7 @@ static void CodeIso14443bAsReader(const uint8_t *cmd, int len)
 		ToSendStuffBit(1);
 	}
 	// Send SOF
-	for(i = 0; i < 10; i++) {
+	for(i = 0; i < 11; i++) {
 		ToSendStuffBit(0);
 	}
 
@@ -865,7 +889,7 @@ static void CodeIso14443bAsReader(const uint8_t *cmd, int len)
 	}
 	// Send EOF
 	ToSendStuffBit(1);
-	for(i = 0; i < 10; i++) {
+	for(i = 0; i < 11; i++) {
 		ToSendStuffBit(0);
 	}
 	for(i = 0; i < 8; i++) {
@@ -874,7 +898,7 @@ static void CodeIso14443bAsReader(const uint8_t *cmd, int len)
 
 	// And then a little more, to make sure that the last character makes
 	// it out before we switch to rx mode.
-	for(i = 0; i < 24; i++) {
+	for(i = 0; i < 10; i++) {
 		ToSendStuffBit(1);
 	}
 
@@ -896,6 +920,103 @@ static void CodeAndTransmit14443bAsReader(const uint8_t *cmd, int len)
 	}
 }
 
+/* Sends an APDU to the tag
+ * TODO: check CRC and preamble
+ */
+int iso14443b_apdu(uint8_t const *message, size_t message_length, uint8_t *response)
+{
+	uint8_t message_frame[message_length + 4];
+	// PCB
+	message_frame[0] = 0x0A | pcb_blocknum;
+	pcb_blocknum ^= 1;
+	// CID
+	message_frame[1] = 0;
+	// INF
+	memcpy(message_frame + 2, message, message_length);
+	// EDC (CRC)
+	ComputeCrc14443(CRC_14443_B, message_frame, message_length + 2, &message_frame[message_length + 2], &message_frame[message_length + 3]);
+	// send
+	CodeAndTransmit14443bAsReader(message_frame, message_length + 4);
+	// get response
+	GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT*100, TRUE);
+	if(Demod.len < 3)
+	{
+		return 0;
+	}
+	// TODO: Check CRC
+	// copy response contents
+	if(response != NULL)
+	{
+		memcpy(response, Demod.output, Demod.len);
+	}
+	return Demod.len;
+}
+
+/* Perform the ISO 14443 B Card Selection procedure
+ * Currently does NOT do any collision handling.
+ * It expects 0-1 cards in the device's range.
+ * TODO: Support multiple cards (perform anticollision)
+ * TODO: Verify CRC checksums
+ */
+int iso14443b_select_card()
+{
+	// WUPB command (including CRC)
+	// Note: WUPB wakes up all tags, REQB doesn't wake up tags in HALT state
+	static const uint8_t wupb[] = { 0x05, 0x00, 0x08, 0x39, 0x73 };
+	// ATTRIB command (with space for CRC)
+	uint8_t attrib[] = { 0x1D, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00};
+
+	// first, wake up the tag
+	CodeAndTransmit14443bAsReader(wupb, sizeof(wupb));
+	GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
+	// ATQB too short?
+	if (Demod.len < 14)
+	{
+		return 2;
+	}
+
+    // select the tag
+    // copy the PUPI to ATTRIB
+    memcpy(attrib + 1, Demod.output + 1, 4);
+    /* copy the protocol info from ATQB (Protocol Info -> Protocol_Type) into
+    ATTRIB (Param 3) */
+    attrib[7] = Demod.output[10] & 0x0F;
+    ComputeCrc14443(CRC_14443_B, attrib, 9, attrib + 9, attrib + 10);
+    CodeAndTransmit14443bAsReader(attrib, sizeof(attrib));
+    GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
+    // Answer to ATTRIB too short?
+    if(Demod.len < 3)
+	{
+		return 2;
+	}
+	// reset PCB block number
+	pcb_blocknum = 0;
+	return 1;
+}
+
+// Set up ISO 14443 Type B communication (similar to iso14443a_setup)
+void iso14443b_setup() {
+
+	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+
+	BigBuf_free();
+	// Set up the synchronous serial port
+	FpgaSetupSsc();
+	// connect Demodulated Signal to ADC:
+	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
+
+	// Signal field is on with the appropriate LED
+    LED_D_ON();
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX | FPGA_HF_READER_TX_SHALLOW_MOD);
+	
+	//SpinDelay(100);
+
+	// Start the timer
+	//StartCountSspClk();
+
+	DemodReset();
+	UartReset();
+}
 
 //-----------------------------------------------------------------------------
 // Read a SRI512 ISO 14443B tag.
@@ -908,12 +1029,14 @@ static void CodeAndTransmit14443bAsReader(const uint8_t *cmd, int len)
 //-----------------------------------------------------------------------------
 void ReadSTMemoryIso14443b(uint32_t dwLast)
 {
+	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
+	BigBuf_free();
+
 	clear_trace();
 	set_tracing(TRUE);
 
 	uint8_t i = 0x00;
 
-	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
 	// Make sure that we start from off, since the tags are stateful;
 	// confusing things will happen if we don't reset them between reads.
 	LED_D_OFF();
@@ -936,6 +1059,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 
 	if (Demod.len == 0) {
 		DbpString("No response from tag");
+		set_tracing(FALSE);	
 		return;
 	} else {
 		Dbprintf("Randomly generated Chip ID (+ 2 byte CRC): %02x %02x %02x",
@@ -951,17 +1075,20 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 	GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
 	if (Demod.len != 3) {
 		Dbprintf("Expected 3 bytes from tag, got %d", Demod.len);
+		set_tracing(FALSE);	
 		return;
 	}
 	// Check the CRC of the answer:
 	ComputeCrc14443(CRC_14443_B, Demod.output, 1 , &cmd1[2], &cmd1[3]);
 	if(cmd1[2] != Demod.output[1] || cmd1[3] != Demod.output[2]) {
 		DbpString("CRC Error reading select response.");
+		set_tracing(FALSE);	
 		return;
 	}
 	// Check response from the tag: should be the same UID as the command we just sent:
 	if (cmd1[1] != Demod.output[0]) {
 		Dbprintf("Bad response to SELECT from Tag, aborting: %02x %02x", cmd1[1], Demod.output[0]);
+		set_tracing(FALSE);	
 		return;
 	}
 
@@ -973,6 +1100,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 	GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
 	if (Demod.len != 10) {
 		Dbprintf("Expected 10 bytes from tag, got %d", Demod.len);
+		set_tracing(FALSE);	
 		return;
 	}
 	// The check the CRC of the answer (use cmd1 as temporary variable):
@@ -980,7 +1108,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 	if(cmd1[2] != Demod.output[8] || cmd1[3] != Demod.output[9]) {
 		Dbprintf("CRC Error reading block! Expected: %04x got: %04x",
 				(cmd1[2]<<8)+cmd1[3], (Demod.output[8]<<8)+Demod.output[9]);
-		// Do not return;, let's go on... (we should retry, maybe ?)
+	// Do not return;, let's go on... (we should retry, maybe ?)
 	}
 	Dbprintf("Tag UID (64 bits): %08x %08x",
 			(Demod.output[7]<<24) + (Demod.output[6]<<16) + (Demod.output[5]<<8) + Demod.output[4],
@@ -992,7 +1120,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 	i = 0x00;
 	dwLast++;
 	for (;;) {
-		if (i == dwLast) {
+		   if (i == dwLast) {
 			DbpString("System area block (0xff):");
 			i = 0xff;
 		}
@@ -1001,15 +1129,15 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 		CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
 		GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
 		if (Demod.len != 6) { // Check if we got an answer from the tag
-			DbpString("Expected 6 bytes from tag, got less...");
-			return;
+		DbpString("Expected 6 bytes from tag, got less...");
+		return;
 		}
 		// The check the CRC of the answer (use cmd1 as temporary variable):
 		ComputeCrc14443(CRC_14443_B, Demod.output, 4, &cmd1[2], &cmd1[3]);
-		if(cmd1[2] != Demod.output[4] || cmd1[3] != Demod.output[5]) {
+			if(cmd1[2] != Demod.output[4] || cmd1[3] != Demod.output[5]) {
 			Dbprintf("CRC Error reading block! Expected: %04x got: %04x",
 					(cmd1[2]<<8)+cmd1[3], (Demod.output[4]<<8)+Demod.output[5]);
-			// Do not return;, let's go on... (we should retry, maybe ?)
+		// Do not return;, let's go on... (we should retry, maybe ?)
 		}
 		// Now print out the memory location:
 		Dbprintf("Address=%02x, Contents=%08x, CRC=%04x", i,
@@ -1020,6 +1148,8 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
 		}
 		i++;
 	}
+	
+	set_tracing(FALSE);
 }
 
 
@@ -1090,7 +1220,7 @@ void RAMFUNC SnoopIso14443b(void)
 
 	bool TagIsActive = FALSE;
 	bool ReaderIsActive = FALSE;
-	
+		
 	// And now we loop, receiving samples.
 	for(;;) {
 		int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) &
@@ -1129,49 +1259,51 @@ void RAMFUNC SnoopIso14443b(void)
 
 		if (!TagIsActive) {							// no need to try decoding reader data if the tag is sending
 			if(Handle14443bUartBit(ci & 0x01)) {
-				if(triggered && tracing) {
+			if(triggered && tracing) {
 					LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE);
-				}
-				/* And ready to receive another command. */
-				UartReset();
-				/* And also reset the demod code, which might have been */
-				/* false-triggered by the commands from the reader. */
-				DemodReset();
 			}
+			/* And ready to receive another command. */
+			UartReset();
+			/* And also reset the demod code, which might have been */
+			/* false-triggered by the commands from the reader. */
+			DemodReset();
+		}
 			if(Handle14443bUartBit(cq & 0x01)) {
-				if(triggered && tracing) {
+			if(triggered && tracing) {
 					LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE);
-				}
-				/* And ready to receive another command. */
-				UartReset();
-				/* And also reset the demod code, which might have been */
-				/* false-triggered by the commands from the reader. */
-				DemodReset();
 			}
+			/* And ready to receive another command. */
+			UartReset();
+			/* And also reset the demod code, which might have been */
+			/* false-triggered by the commands from the reader. */
+			DemodReset();
+		}
 			ReaderIsActive = (Uart.state > STATE_GOT_FALLING_EDGE_OF_SOF);
 		}
 
 		if(!ReaderIsActive) {						// no need to try decoding tag data if the reader is sending - and we cannot afford the time
-			if(Handle14443bSamplesDemod(ci | 0x01, cq | 0x01)) {
-
-				//Use samples as a time measurement
-				if(tracing)
-				{
-					uint8_t parity[MAX_PARITY_SIZE];
-					LogTrace(Demod.output, Demod.len, samples, samples, parity, FALSE);
-				}
-				triggered = TRUE;
-
-				// And ready to receive another response.
-				DemodReset();
+			// is this | 0x01 the error?   & 0xfe  in https://github.com/Proxmark/proxmark3/issues/103
+			if(Handle14443bSamplesDemod(ci & 0xfe, cq & 0xfe)) {
+
+			//Use samples as a time measurement
+			if(tracing)
+			{
+				//uint8_t parity[MAX_PARITY_SIZE];
+				LogTrace(Demod.output, Demod.len, samples, samples, parity, FALSE);
 			}
+			triggered = TRUE;
+
+			// And ready to receive another response.
+			DemodReset();
+		}
 			TagIsActive = (Demod.state > DEMOD_GOT_FALLING_EDGE_OF_SOF);
 		}
-
 	}
 
 	FpgaDisableSscDma();
 	LEDsoff();
+	set_tracing(FALSE);	
+		
 	AT91C_BASE_PDC_SSC->PDC_PTCR = AT91C_PDC_RXTDIS;
 	DbpString("Snoop statistics:");
 	Dbprintf("  Max behind by: %i", maxBehindBy);
@@ -1196,22 +1328,25 @@ void RAMFUNC SnoopIso14443b(void)
  */
 void SendRawCommand14443B(uint32_t datalen, uint32_t recv, uint8_t powerfield, uint8_t data[])
 {
-	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
-	FpgaSetupSsc();
-
-	set_tracing(TRUE);
+	iso14443b_setup();
 	
-	CodeAndTransmit14443bAsReader(data, datalen);
+	if ( datalen == 0 && recv == 0 && powerfield == 0){
+		
+	} else {		
+		set_tracing(TRUE);
+		CodeAndTransmit14443bAsReader(data, datalen);
+	}
 
 	if(recv) {
-		GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
+		GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, FALSE);
 		uint16_t iLen = MIN(Demod.len, USB_CMD_DATA_SIZE);
 		cmd_send(CMD_ACK, iLen, 0, 0, Demod.output, iLen);
 	}
 	
 	if(!powerfield) {
 		FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
+		FpgaDisableSscDma();
+		set_tracing(FALSE);
 		LED_D_OFF();
 	}
 }