[proxmark3-svn] / armsrc / lfsampling.c

//-----------------------------------------------------------------------------
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// Miscellaneous routines for low frequency sampling.
//-----------------------------------------------------------------------------

#include "lfsampling.h"

/*
Default LF config is set to:
	decimation = 1  (we keep 1 out of 1 samples)
	bits_per_sample = 8
	averaging = YES
	divisor = 95 (125khz)
	trigger_threshold = 0
	*/
sample_config config = { 1, 8, 1, 95, 0 } ;

void printConfig() {
	Dbprintf("LF Sampling config: ");
	Dbprintf("  [q] divisor:           %d (%d KHz)", config.divisor, 12000 / (config.divisor+1));
	Dbprintf("  [b] bps:               %d ", config.bits_per_sample);
	Dbprintf("  [d] decimation:        %d ", config.decimation);
	Dbprintf("  [a] averaging:         %s ", (config.averaging) ? "Yes" : "No");
	Dbprintf("  [t] trigger threshold: %d ", config.trigger_threshold);
}

/**
 * Called from the USB-handler to set the sampling configuration
 * The sampling config is used for std reading and snooping.
 *
 * Other functions may read samples and ignore the sampling config,
 * such as functions to read the UID from a prox tag or similar.
 *
 * Values set to '0' implies no change (except for averaging)
 * @brief setSamplingConfig
 * @param sc
 */
void setSamplingConfig(sample_config *sc) {
	if(sc->divisor != 0) config.divisor = sc->divisor;
	if(sc->bits_per_sample != 0) config.bits_per_sample = sc->bits_per_sample;
	if(sc->trigger_threshold != -1) config.trigger_threshold = sc->trigger_threshold;
	
	config.decimation = (sc->decimation != 0) ? sc->decimation : 1;
	config.averaging = sc->averaging;
	if(config.bits_per_sample > 8)	config.bits_per_sample = 8;

	printConfig();
}

sample_config* getSamplingConfig() {
	return &config;
}

struct BitstreamOut {
	uint8_t * buffer;
	uint32_t numbits;
	uint32_t position;
};

/**
 * @brief Pushes bit onto the stream
 * @param stream
 * @param bit
 */
void pushBit( BitstreamOut* stream, uint8_t bit) {
	int bytepos = stream->position >> 3; // divide by 8
	int bitpos = stream->position & 7;
	*(stream->buffer+bytepos) |= (bit > 0) <<  (7 - bitpos);
	stream->position++;
	stream->numbits++;
}

/**
* Setup the FPGA to listen for samples. This method downloads the FPGA bitstream
* if not already loaded, sets divisor and starts up the antenna.
* @param divisor : 1, 88> 255 or negative ==> 134.8 KHz
* 				   0 or 95 ==> 125 KHz
*
**/
void LFSetupFPGAForADC(int divisor, bool lf_field) {
	FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
	if ( (divisor == 1) || (divisor < 0) || (divisor > 255) )
		FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz
	else if (divisor == 0)
		FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
	else
		FpgaSendCommand(FPGA_CMD_SET_DIVISOR, divisor);

	FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC | (lf_field ? FPGA_LF_ADC_READER_FIELD : 0));

	// Connect the A/D to the peak-detected low-frequency path.
	SetAdcMuxFor(GPIO_MUXSEL_LOPKD);
	// 50ms for the resonant antenna to settle.
	SpinDelay(50);
	// Now set up the SSC to get the ADC samples that are now streaming at us.
	FpgaSetupSsc();
	// start a 1.5ticks is 1us
	StartTicks();
}

/**
 * Does the sample acquisition. If threshold is specified, the actual sampling
 * is not commenced until the threshold has been reached.
 * This method implements decimation and quantization in order to
 * be able to provide longer sample traces.
 * Uses the following global settings:
 * @param decimation - how much should the signal be decimated. A decimation of N means we keep 1 in N samples, etc.
 * @param bits_per_sample - bits per sample. Max 8, min 1 bit per sample.
 * @param averaging If set to true, decimation will use averaging, so that if e.g. decimation is 3, the sample
 * value that will be used is the average value of the three samples.
 * @param trigger_threshold - a threshold. The sampling won't commence until this threshold has been reached. Set
 * to -1 to ignore threshold.
 * @param silent - is true, now outputs are made. If false, dbprints the status
 * @return the number of bits occupied by the samples.
 */
uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averaging, int trigger_threshold, bool silent, int bufsize) {
	//bigbuf, to hold the aquired raw data signal
	uint8_t *dest = BigBuf_get_addr();
    bufsize = (bufsize > 0 && bufsize < BigBuf_max_traceLen()) ? bufsize : BigBuf_max_traceLen();

	//BigBuf_Clear_ext(false);	  //creates issues with cmdread (marshmellow)

	if(bits_per_sample < 1) bits_per_sample = 1;
	if(bits_per_sample > 8) bits_per_sample = 8;

	if(decimation < 1) decimation = 1;

	// Use a bit stream to handle the output
	BitstreamOut data = { dest , 0, 0};
	int sample_counter = 0;
	uint8_t sample = 0;
	//If we want to do averaging
	uint32_t sample_sum =0 ;
	uint32_t sample_total_numbers =0 ;
	uint32_t sample_total_saved =0 ;

	while(!BUTTON_PRESS() && !usb_poll_validate_length() ) {
		WDT_HIT();
		if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
			AT91C_BASE_SSC->SSC_THR = 0x43;
			LED_D_ON();
		}
		if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
			sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
			LED_D_OFF();
			// threshold either high or low values 128 = center 0.  if trigger = 178 
			if ((trigger_threshold > 0) && (sample < (trigger_threshold+128)) && (sample > (128-trigger_threshold))) // 
				continue;

			trigger_threshold = 0;
			sample_total_numbers++;

			if(averaging)
			{
				sample_sum += sample;
			}
			//Check decimation
			if(decimation > 1)
			{
				sample_counter++;
				if(sample_counter < decimation) continue;
				sample_counter = 0;
			}
			//Averaging
			if(averaging && decimation > 1) {
				sample = sample_sum / decimation;
				sample_sum =0;
			}
			//Store the sample
			sample_total_saved ++;
			if(bits_per_sample == 8){
				dest[sample_total_saved-1] = sample;
				data.numbits = sample_total_saved << 3;//Get the return value correct
				if(sample_total_saved >= bufsize) break;
			}
			else{
				pushBit(&data, sample & 0x80);
				if(bits_per_sample > 1)	pushBit(&data, sample & 0x40);
				if(bits_per_sample > 2)	pushBit(&data, sample & 0x20);
				if(bits_per_sample > 3)	pushBit(&data, sample & 0x10);
				if(bits_per_sample > 4)	pushBit(&data, sample & 0x08);
				if(bits_per_sample > 5)	pushBit(&data, sample & 0x04);
				if(bits_per_sample > 6)	pushBit(&data, sample & 0x02);
				//Not needed, 8bps is covered above
				//if(bits_per_sample > 7)	pushBit(&data, sample & 0x01);
				if((data.numbits >> 3) +1  >= bufsize) break;
			}
		}
	}

	if(!silent)
	{
		Dbprintf("Done, saved %d out of %d seen samples at %d bits/sample",sample_total_saved, sample_total_numbers,bits_per_sample);
		Dbprintf("buffer samples: %02x %02x %02x %02x %02x %02x %02x %02x ...",
					dest[0], dest[1], dest[2], dest[3], dest[4], dest[5], dest[6], dest[7]);
	}
	return data.numbits;
}
/**
 * @brief Does sample acquisition, ignoring the config values set in the sample_config.
 * This method is typically used by tag-specific readers who just wants to read the samples
 * the normal way
 * @param trigger_threshold
 * @param silent
 * @return number of bits sampled
 */
uint32_t DoAcquisition_default(int trigger_threshold, bool silent) {
	return DoAcquisition(1, 8, 0,trigger_threshold, silent, 0);
}
uint32_t DoAcquisition_config( bool silent) {
	return DoAcquisition(config.decimation
				  ,config.bits_per_sample
				  ,config.averaging
				  ,config.trigger_threshold
				  ,silent
				  ,0);
}

uint32_t DoPartialAcquisition(int trigger_threshold, bool silent, int sample_size) {
	return DoAcquisition(1, 8, 0, trigger_threshold, silent, sample_size);
}

uint32_t ReadLF(bool activeField, bool silent) {
	if (!silent)
		printConfig();
	LFSetupFPGAForADC(config.divisor, activeField);
	return DoAcquisition_config(silent);
}

/**
* Initializes the FPGA for reader-mode (field on), and acquires the samples.
* @return number of bits sampled
**/
uint32_t SampleLF(bool printCfg) {
	BigBuf_Clear_ext(false);
	uint32_t ret = ReadLF(true, printCfg);
	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
	return ret;	
}
/**
* Initializes the FPGA for snoop-mode (field off), and acquires the samples.
* @return number of bits sampled
**/
uint32_t SnoopLF() {
	BigBuf_Clear_ext(false);
	uint32_t ret = ReadLF(false, true);
	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
	return ret;	
}

/**
* acquisition of T55x7 LF signal. Similart to other LF, but adjusted with @marshmellows thresholds
* the data is collected in BigBuf.
**/
void doT55x7Acquisition(size_t sample_size) {

	#define T55xx_READ_UPPER_THRESHOLD 128+60  // 60 grph
	#define T55xx_READ_LOWER_THRESHOLD 128-60  // -60 grph
	#define T55xx_READ_TOL   5
	
	uint8_t *dest = BigBuf_get_addr();
	uint16_t bufsize = BigBuf_max_traceLen();
	
	if ( bufsize > sample_size )
		bufsize = sample_size;

	uint8_t curSample = 0, lastSample = 0;
	uint16_t i = 0, skipCnt = 0;
	bool startFound = false;
	bool highFound = false;
	bool lowFound = false;
		
	while(!BUTTON_PRESS() && !usb_poll_validate_length() && skipCnt < 1000 && (i < bufsize) ) {
		WDT_HIT();		
		if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
			AT91C_BASE_SSC->SSC_THR = 0x43; //43
			LED_D_ON();
		}
		if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
			curSample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;	
			LED_D_OFF();
		
			// skip until the first high sample above threshold
			if (!startFound && curSample > T55xx_READ_UPPER_THRESHOLD) {
				//if (curSample > lastSample) 
				//	lastSample = curSample;
				highFound = true;
			} else if (!highFound) {
				skipCnt++;
				continue;
			}
			// skip until the first low sample below threshold
			if (!startFound && curSample < T55xx_READ_LOWER_THRESHOLD) {
				//if (curSample > lastSample) 
				lastSample = curSample;
				lowFound = true;
			} else if (!lowFound) {
				skipCnt++;
				continue;
			}

			// skip until first high samples begin to change
			if (startFound || curSample > T55xx_READ_LOWER_THRESHOLD + T55xx_READ_TOL){
				// if just found start - recover last sample
				if (!startFound) {
					dest[i++] = lastSample;
					startFound = true;
				}
				// collect samples
				dest[i++] = curSample;
			}
		}
	}
}
/**
* acquisition of Cotag LF signal. Similart to other LF,  since the Cotag has such long datarate RF/384
* and is Manchester?,  we directly gather the manchester data into bigbuff
**/

#define COTAG_T1 384
#define COTAG_T2 (COTAG_T1>>1)
#define COTAG_ONE_THRESHOLD 128+30
#define COTAG_ZERO_THRESHOLD 128-30
#ifndef COTAG_BITS
#define COTAG_BITS 264
#endif
void doCotagAcquisition(size_t sample_size) {

	uint8_t *dest = BigBuf_get_addr();
	uint16_t bufsize = BigBuf_max_traceLen();
	
	if ( bufsize > sample_size )
		bufsize = sample_size;

	dest[0] = 0;	
	uint8_t sample = 0, firsthigh = 0, firstlow = 0; 
	uint16_t i = 0;

	while (!BUTTON_PRESS() && !usb_poll_validate_length() && (i < bufsize) ) {
		WDT_HIT();		
		if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
			AT91C_BASE_SSC->SSC_THR = 0x43;
			LED_D_ON();
		}
		
		if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
			sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;	
			LED_D_OFF();
		
			// find first peak
			if ( !firsthigh ) {
				if (sample < COTAG_ONE_THRESHOLD) 
					continue;
				firsthigh = 1;
			}
			if ( !firstlow ){
				if (sample > COTAG_ZERO_THRESHOLD )
					continue;
				firstlow = 1;
			}

			++i;			
	
			if ( sample > COTAG_ONE_THRESHOLD)
				dest[i] = 255;
			else if ( sample < COTAG_ZERO_THRESHOLD) 
				dest[i] = 0;
			else 
				dest[i] = dest[i-1];			
		}
	}
}

uint32_t doCotagAcquisitionManchester() {

	uint8_t *dest = BigBuf_get_addr();
	uint16_t bufsize = BigBuf_max_traceLen();
	
	if ( bufsize > COTAG_BITS )
		bufsize = COTAG_BITS;

	dest[0] = 0;	
	uint8_t sample = 0, firsthigh = 0, firstlow = 0; 
	uint16_t sample_counter = 0, period = 0;
	uint8_t curr = 0, prev = 0;

	while (!BUTTON_PRESS() && !usb_poll_validate_length() && (sample_counter < bufsize) ) {
		WDT_HIT();		
		if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
			AT91C_BASE_SSC->SSC_THR = 0x43;
			LED_D_ON();
		}
		
		if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
			sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;	
			LED_D_OFF();
		
			// find first peak
			if ( !firsthigh ) {
				if (sample < COTAG_ONE_THRESHOLD) 
					continue;
				firsthigh = 1;
			}
			
			if ( !firstlow ){
				if (sample > COTAG_ZERO_THRESHOLD )
					continue;
				firstlow = 1;
			}
						
			// set sample 255, 0,  or previous			
			if ( sample > COTAG_ONE_THRESHOLD){
				prev = curr;
				curr = 1;
			}
			else if ( sample < COTAG_ZERO_THRESHOLD) {
				prev = curr;
				curr = 0;
			}
			else {
				curr = prev;
			}			

			// full T1 periods, 
			if ( period > 0 ) {
				--period;
				continue;
			}
						
			dest[sample_counter] = curr;
			++sample_counter;
			period = COTAG_T1;
		}
	}
	return sample_counter;
}
Commit	Line	Data
31abe49f MHS	1	//-----------------------------------------------------------------------------
	2	// This code is licensed to you under the terms of the GNU GPL, version 2 or,
	3	// at your option, any later version. See the LICENSE.txt file for the text of
	4	// the license.
	5	//-----------------------------------------------------------------------------
	6	// Miscellaneous routines for low frequency sampling.
	7	//-----------------------------------------------------------------------------
	8
31abe49f	9	#include "lfsampling.h"
10a8875c	10
507afbf3	11	/*
	12	Default LF config is set to:
	13	decimation = 1 (we keep 1 out of 1 samples)
	14	bits_per_sample = 8
	15	averaging = YES
	16	divisor = 95 (125khz)
	17	trigger_threshold = 0
	18	*/
0cd2a41a	19	sample_config config = { 1, 8, 1, 95, 0 } ;
31abe49f	20
24c49d36	21	void printConfig() {
7838f4be	22	Dbprintf("LF Sampling config: ");
5f5b83b7	23	Dbprintf(" [q] divisor: %d (%d KHz)", config.divisor, 12000 / (config.divisor+1));
31abe49f MHS	24	Dbprintf(" [b] bps: %d ", config.bits_per_sample);
31abe49f MHS	25	Dbprintf(" [d] decimation: %d ", config.decimation);
507afbf3	26	Dbprintf(" [a] averaging: %s ", (config.averaging) ? "Yes" : "No");
31abe49f MHS	27	Dbprintf(" [t] trigger threshold: %d ", config.trigger_threshold);
	28	}
	29
31abe49f MHS	30	/**
	31	* Called from the USB-handler to set the sampling configuration
	32	* The sampling config is used for std reading and snooping.
	33	*
	34	* Other functions may read samples and ignore the sampling config,
	35	* such as functions to read the UID from a prox tag or similar.
	36	*
	37	* Values set to '0' implies no change (except for averaging)
	38	* @brief setSamplingConfig
	39	* @param sc
	40	*/
24c49d36	41	void setSamplingConfig(sample_config *sc) {
31abe49f	42	if(sc->divisor != 0) config.divisor = sc->divisor;
9974991e	43	if(sc->bits_per_sample != 0) config.bits_per_sample = sc->bits_per_sample;
9974991e	44	if(sc->trigger_threshold != -1) config.trigger_threshold = sc->trigger_threshold;
507afbf3	45
507afbf3	46	config.decimation = (sc->decimation != 0) ? sc->decimation : 1;
9974991e	47	config.averaging = sc->averaging;
31abe49f	48	if(config.bits_per_sample > 8) config.bits_per_sample = 8;
31abe49f MHS	49
	50	printConfig();
	51	}
	52
24c49d36	53	sample_config* getSamplingConfig() {
31abe49f MHS	54	return &config;
31abe49f MHS	55	}
10a8875c	56
53d5dc64	57	struct BitstreamOut {
31abe49f MHS	58	uint8_t * buffer;
	59	uint32_t numbits;
	60	uint32_t position;
53d5dc64	61	};
31abe49f	62
31abe49f MHS	63	/**
	64	* @brief Pushes bit onto the stream
	65	* @param stream
	66	* @param bit
	67	*/
24c49d36	68	void pushBit( BitstreamOut* stream, uint8_t bit) {
31abe49f MHS	69	int bytepos = stream->position >> 3; // divide by 8
	70	int bitpos = stream->position & 7;
	71	*(stream->buffer+bytepos) \|= (bit > 0) << (7 - bitpos);
	72	stream->position++;
	73	stream->numbits++;
	74	}
10a8875c	75
31abe49f MHS	76	/**
	77	* Setup the FPGA to listen for samples. This method downloads the FPGA bitstream
	78	* if not already loaded, sets divisor and starts up the antenna.
	79	* @param divisor : 1, 88> 255 or negative ==> 134.8 KHz
	80	* 0 or 95 ==> 125 KHz
	81	*
	82	**/
24c49d36	83	void LFSetupFPGAForADC(int divisor, bool lf_field) {
31abe49f MHS	84	FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
	85	if ( (divisor == 1) \|\| (divisor < 0) \|\| (divisor > 255) )
	86	FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz
	87	else if (divisor == 0)
	88	FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
	89	else
	90	FpgaSendCommand(FPGA_CMD_SET_DIVISOR, divisor);
	91
	92	FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC \| (lf_field ? FPGA_LF_ADC_READER_FIELD : 0));
	93
	94	// Connect the A/D to the peak-detected low-frequency path.
	95	SetAdcMuxFor(GPIO_MUXSEL_LOPKD);
8255e1a6	96	// 50ms for the resonant antenna to settle.
31abe49f MHS	97	SpinDelay(50);
	98	// Now set up the SSC to get the ADC samples that are now streaming at us.
	99	FpgaSetupSsc();
24c49d36	100	// start a 1.5ticks is 1us
24c49d36	101	StartTicks();
31abe49f MHS	102	}
31abe49f MHS	103
31abe49f MHS	104	/**
	105	* Does the sample acquisition. If threshold is specified, the actual sampling
	106	* is not commenced until the threshold has been reached.
	107	* This method implements decimation and quantization in order to
	108	* be able to provide longer sample traces.
	109	* Uses the following global settings:
	110	* @param decimation - how much should the signal be decimated. A decimation of N means we keep 1 in N samples, etc.
	111	* @param bits_per_sample - bits per sample. Max 8, min 1 bit per sample.
	112	* @param averaging If set to true, decimation will use averaging, so that if e.g. decimation is 3, the sample
	113	* value that will be used is the average value of the three samples.
	114	* @param trigger_threshold - a threshold. The sampling won't commence until this threshold has been reached. Set
	115	* to -1 to ignore threshold.
	116	* @param silent - is true, now outputs are made. If false, dbprints the status
	117	* @return the number of bits occupied by the samples.
	118	*/
17556415	119	uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averaging, int trigger_threshold, bool silent, int bufsize) {
1c8fbeb9	120	//bigbuf, to hold the aquired raw data signal
0644d5e3	121	uint8_t *dest = BigBuf_get_addr();
17556415	122	bufsize = (bufsize > 0 && bufsize < BigBuf_max_traceLen()) ? bufsize : BigBuf_max_traceLen();
0644d5e3	123
c0f15a05	124	//BigBuf_Clear_ext(false); //creates issues with cmdread (marshmellow)
31abe49f MHS	125
	126	if(bits_per_sample < 1) bits_per_sample = 1;
	127	if(bits_per_sample > 8) bits_per_sample = 8;
	128
	129	if(decimation < 1) decimation = 1;
	130
	131	// Use a bit stream to handle the output
	132	BitstreamOut data = { dest , 0, 0};
	133	int sample_counter = 0;
	134	uint8_t sample = 0;
	135	//If we want to do averaging
	136	uint32_t sample_sum =0 ;
	137	uint32_t sample_total_numbers =0 ;
	138	uint32_t sample_total_saved =0 ;
	139
edaf10af	140	while(!BUTTON_PRESS() && !usb_poll_validate_length() ) {
31abe49f MHS	141	WDT_HIT();
31abe49f MHS	142	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
5f5b83b7	143	AT91C_BASE_SSC->SSC_THR = 0x43;
31abe49f MHS	144	LED_D_ON();
	145	}
	146	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
	147	sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
	148	LED_D_OFF();
99cf19d9	149	// threshold either high or low values 128 = center 0. if trigger = 178
99cf19d9	150	if ((trigger_threshold > 0) && (sample < (trigger_threshold+128)) && (sample > (128-trigger_threshold))) //
31abe49f MHS	151	continue;
	152
	153	trigger_threshold = 0;
	154	sample_total_numbers++;
	155
	156	if(averaging)
	157	{
	158	sample_sum += sample;
	159	}
	160	//Check decimation
	161	if(decimation > 1)
	162	{
	163	sample_counter++;
	164	if(sample_counter < decimation) continue;
	165	sample_counter = 0;
	166	}
	167	//Averaging
	168	if(averaging && decimation > 1) {
	169	sample = sample_sum / decimation;
	170	sample_sum =0;
	171	}
	172	//Store the sample
	173	sample_total_saved ++;
	174	if(bits_per_sample == 8){
	175	dest[sample_total_saved-1] = sample;
	176	data.numbits = sample_total_saved << 3;//Get the return value correct
	177	if(sample_total_saved >= bufsize) break;
	178	}
	179	else{
	180	pushBit(&data, sample & 0x80);
	181	if(bits_per_sample > 1) pushBit(&data, sample & 0x40);
	182	if(bits_per_sample > 2) pushBit(&data, sample & 0x20);
	183	if(bits_per_sample > 3) pushBit(&data, sample & 0x10);
	184	if(bits_per_sample > 4) pushBit(&data, sample & 0x08);
	185	if(bits_per_sample > 5) pushBit(&data, sample & 0x04);
	186	if(bits_per_sample > 6) pushBit(&data, sample & 0x02);
	187	//Not needed, 8bps is covered above
	188	//if(bits_per_sample > 7) pushBit(&data, sample & 0x01);
	189	if((data.numbits >> 3) +1 >= bufsize) break;
	190	}
	191	}
	192	}
	193
	194	if(!silent)
	195	{
	196	Dbprintf("Done, saved %d out of %d seen samples at %d bits/sample",sample_total_saved, sample_total_numbers,bits_per_sample);
	197	Dbprintf("buffer samples: %02x %02x %02x %02x %02x %02x %02x %02x ...",
	198	dest[0], dest[1], dest[2], dest[3], dest[4], dest[5], dest[6], dest[7]);
	199	}
	200	return data.numbits;
	201	}
	202	/**
	203	* @brief Does sample acquisition, ignoring the config values set in the sample_config.
	204	* This method is typically used by tag-specific readers who just wants to read the samples
	205	* the normal way
	206	* @param trigger_threshold
	207	* @param silent
	208	* @return number of bits sampled
	209	*/
24c49d36	210	uint32_t DoAcquisition_default(int trigger_threshold, bool silent) {
17556415	211	return DoAcquisition(1, 8, 0,trigger_threshold, silent, 0);
31abe49f	212	}
24c49d36	213	uint32_t DoAcquisition_config( bool silent) {
31abe49f MHS	214	return DoAcquisition(config.decimation
	215	,config.bits_per_sample
	216	,config.averaging
	217	,config.trigger_threshold
17556415	218	,silent
	219	,0);
	220	}
	221
	222	uint32_t DoPartialAcquisition(int trigger_threshold, bool silent, int sample_size) {
	223	return DoAcquisition(1, 8, 0, trigger_threshold, silent, sample_size);
31abe49f MHS	224	}
31abe49f MHS	225
24c49d36	226	uint32_t ReadLF(bool activeField, bool silent) {
	227	if (!silent)
	228	printConfig();
31abe49f	229	LFSetupFPGAForADC(config.divisor, activeField);
1fbf8956	230	return DoAcquisition_config(silent);
31abe49f MHS	231	}
	232
	233	/**
	234	* Initializes the FPGA for reader-mode (field on), and acquires the samples.
	235	* @return number of bits sampled
	236	**/
24c49d36	237	uint32_t SampleLF(bool printCfg) {
b828a4e1	238	BigBuf_Clear_ext(false);
	239	uint32_t ret = ReadLF(true, printCfg);
	240	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
	241	return ret;
31abe49f MHS	242	}
	243	/**
	244	* Initializes the FPGA for snoop-mode (field off), and acquires the samples.
	245	* @return number of bits sampled
	246	**/
ac2df346	247	uint32_t SnoopLF() {
b828a4e1	248	BigBuf_Clear_ext(false);
	249	uint32_t ret = ReadLF(false, true);
	250	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
	251	return ret;
31abe49f	252	}
ac2df346	253
	254	/**
	255	* acquisition of T55x7 LF signal. Similart to other LF, but adjusted with @marshmellows thresholds
	256	* the data is collected in BigBuf.
	257	**/
94422fa2	258	void doT55x7Acquisition(size_t sample_size) {
ac2df346	259
17556415	260	#define T55xx_READ_UPPER_THRESHOLD 128+60 // 60 grph
	261	#define T55xx_READ_LOWER_THRESHOLD 128-60 // -60 grph
	262	#define T55xx_READ_TOL 5
24c49d36	263
ac2df346	264	uint8_t *dest = BigBuf_get_addr();
	265	uint16_t bufsize = BigBuf_max_traceLen();
	266
94422fa2	267	if ( bufsize > sample_size )
94422fa2	268	bufsize = sample_size;
ac2df346	269
24c49d36	270	uint8_t curSample = 0, lastSample = 0;
24c49d36	271	uint16_t i = 0, skipCnt = 0;
ac2df346	272	bool startFound = false;
ac2df346	273	bool highFound = false;
6426f6ba	274	bool lowFound = false;
24c49d36	275
3f267966	276	while(!BUTTON_PRESS() && !usb_poll_validate_length() && skipCnt < 1000 && (i < bufsize) ) {
1c8fbeb9	277	WDT_HIT();
ac2df346	278	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
53d5dc64	279	AT91C_BASE_SSC->SSC_THR = 0x43; //43
ac2df346	280	LED_D_ON();
	281	}
	282	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
1d0ccbe0	283	curSample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
1c8fbeb9	284	LED_D_OFF();
1c8fbeb9	285
94422fa2	286	// skip until the first high sample above threshold
1d0ccbe0	287	if (!startFound && curSample > T55xx_READ_UPPER_THRESHOLD) {
6426f6ba	288	//if (curSample > lastSample)
6426f6ba	289	// lastSample = curSample;
1d0ccbe0	290	highFound = true;
ac2df346	291	} else if (!highFound) {
1d0ccbe0	292	skipCnt++;
ac2df346	293	continue;
ac2df346	294	}
53d5dc64	295	// skip until the first low sample below threshold
6426f6ba	296	if (!startFound && curSample < T55xx_READ_LOWER_THRESHOLD) {
	297	//if (curSample > lastSample)
	298	lastSample = curSample;
	299	lowFound = true;
	300	} else if (!lowFound) {
	301	skipCnt++;
	302	continue;
	303	}
	304
94422fa2	305	// skip until first high samples begin to change
24c49d36	306	if (startFound \|\| curSample > T55xx_READ_LOWER_THRESHOLD + T55xx_READ_TOL){
94422fa2	307	// if just found start - recover last sample
94422fa2	308	if (!startFound) {
6426f6ba	309	dest[i++] = lastSample;
3f267966	310	startFound = true;
94422fa2	311	}
94422fa2	312	// collect samples
1d0ccbe0	313	dest[i++] = curSample;
ac2df346	314	}
	315	}
	316	}
1d0ccbe0	317	}
5f5b83b7	318	/**
	319	* acquisition of Cotag LF signal. Similart to other LF, since the Cotag has such long datarate RF/384
	320	* and is Manchester?, we directly gather the manchester data into bigbuff
	321	**/
	322
	323	#define COTAG_T1 384
	324	#define COTAG_T2 (COTAG_T1>>1)
	325	#define COTAG_ONE_THRESHOLD 128+30
	326	#define COTAG_ZERO_THRESHOLD 128-30
17556415	327	#ifndef COTAG_BITS
	328	#define COTAG_BITS 264
	329	#endif
5f5b83b7	330	void doCotagAcquisition(size_t sample_size) {
	331
	332	uint8_t *dest = BigBuf_get_addr();
	333	uint16_t bufsize = BigBuf_max_traceLen();
	334
	335	if ( bufsize > sample_size )
	336	bufsize = sample_size;
	337
	338	dest[0] = 0;
	339	uint8_t sample = 0, firsthigh = 0, firstlow = 0;
	340	uint16_t i = 0;
	341
	342	while (!BUTTON_PRESS() && !usb_poll_validate_length() && (i < bufsize) ) {
	343	WDT_HIT();
	344	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
	345	AT91C_BASE_SSC->SSC_THR = 0x43;
	346	LED_D_ON();
	347	}
	348
	349	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
	350	sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
	351	LED_D_OFF();
	352
	353	// find first peak
	354	if ( !firsthigh ) {
	355	if (sample < COTAG_ONE_THRESHOLD)
	356	continue;
	357	firsthigh = 1;
	358	}
	359	if ( !firstlow ){
	360	if (sample > COTAG_ZERO_THRESHOLD )
	361	continue;
	362	firstlow = 1;
	363	}
	364
	365	++i;
	366
	367	if ( sample > COTAG_ONE_THRESHOLD)
	368	dest[i] = 255;
	369	else if ( sample < COTAG_ZERO_THRESHOLD)
	370	dest[i] = 0;
	371	else
	372	dest[i] = dest[i-1];
	373	}
	374	}
	375	}
	376
	377	uint32_t doCotagAcquisitionManchester() {
	378
	379	uint8_t *dest = BigBuf_get_addr();
	380	uint16_t bufsize = BigBuf_max_traceLen();
	381
a330987d	382	if ( bufsize > COTAG_BITS )
a330987d	383	bufsize = COTAG_BITS;
5f5b83b7	384
	385	dest[0] = 0;
	386	uint8_t sample = 0, firsthigh = 0, firstlow = 0;
	387	uint16_t sample_counter = 0, period = 0;
	388	uint8_t curr = 0, prev = 0;
	389
	390	while (!BUTTON_PRESS() && !usb_poll_validate_length() && (sample_counter < bufsize) ) {
	391	WDT_HIT();
	392	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
	393	AT91C_BASE_SSC->SSC_THR = 0x43;
	394	LED_D_ON();
	395	}
	396
	397	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
	398	sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
	399	LED_D_OFF();
	400
	401	// find first peak
	402	if ( !firsthigh ) {
	403	if (sample < COTAG_ONE_THRESHOLD)
	404	continue;
	405	firsthigh = 1;
	406	}
	407
	408	if ( !firstlow ){
	409	if (sample > COTAG_ZERO_THRESHOLD )
	410	continue;
	411	firstlow = 1;
	412	}
	413
	414	// set sample 255, 0, or previous
	415	if ( sample > COTAG_ONE_THRESHOLD){
	416	prev = curr;
	417	curr = 1;
	418	}
	419	else if ( sample < COTAG_ZERO_THRESHOLD) {
	420	prev = curr;
	421	curr = 0;
	422	}
	423	else {
	424	curr = prev;
	425	}
	426
	427	// full T1 periods,
	428	if ( period > 0 ) {
	429	--period;
	430	continue;
	431	}
	432
	433	dest[sample_counter] = curr;
	434	++sample_counter;
	435	period = COTAG_T1;
	436	}
	437	}
	438	return sample_counter;
	439	}