[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 "proxmark3.h"
#include "apps.h"
#include "util.h"
#include "string.h"
#include "lfsampling.h"
#include "usb_cdc.h"	// for usb_poll_validate_length
#include "fpgaloader.h"

sample_config config = { 1, 8, 1, 95, 0, 0 } ;

void printConfig()
{
	Dbprintf("LF Sampling config: ");
	Dbprintf("  [q] divisor:           %d ", config.divisor);
	Dbprintf("  [b] bps:               %d ", config.bits_per_sample);
	Dbprintf("  [d] decimation:        %d ", config.decimation);
	Dbprintf("  [a] averaging:         %d ", config.averaging);
	Dbprintf("  [t] trigger threshold: %d ", config.trigger_threshold);
	Dbprintf("  [s] samples to skip:   %d ", config.samples_to_skip);
}


/**
 * 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, threshold, samples_to_skip)
 * @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->decimation!= 0) config.decimation= sc->decimation;
	if(sc->trigger_threshold != -1) config.trigger_threshold= sc->trigger_threshold;
	if(sc->samples_to_skip != -1) config.samples_to_skip = sc->samples_to_skip;

	config.averaging= sc->averaging;
	if(config.bits_per_sample > 8)	config.bits_per_sample = 8;
	if(config.decimation < 1)	config.decimation = 1;

	printConfig();
}

sample_config* getSamplingConfig()
{
	return &config;
}

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

/**
 * @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);
	// Give it a bit of time 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(FPGA_MAJOR_MODE_LF_ADC);
}

/**
 * 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, int cancel_after, int samples_to_skip)
{
	//.
	uint8_t *dest = BigBuf_get_addr();
	bufsize = (bufsize > 0 && bufsize < BigBuf_max_traceLen()) ? bufsize : BigBuf_max_traceLen();

	//memset(dest, 0, bufsize); //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 ;
	uint32_t cancel_counter = 0;
	uint32_t samples_skipped = 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))) { // 
				if (cancel_after > 0) {
					cancel_counter++;
					if (cancel_after == cancel_counter) break;
				}
				continue;
			}
			trigger_threshold = 0;
			if (samples_to_skip > samples_skipped) {
				samples_skipped++;
				continue;
			}
			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,0,0,0);
}
uint32_t DoAcquisition_config(bool silent, int sample_size)
{
	return DoAcquisition(config.decimation
				  ,config.bits_per_sample
				  ,config.averaging
				  ,config.trigger_threshold
				  ,silent
				  ,sample_size
				  ,0
				  ,config.samples_to_skip);
}

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

uint32_t ReadLF(bool activeField, bool silent, int sample_size)
{
	if (!silent) printConfig();
	LFSetupFPGAForADC(config.divisor, activeField);
	// Now call the acquisition routine
	return DoAcquisition_config(silent, sample_size);
}

/**
* Initializes the FPGA for reader-mode (field on), and acquires the samples.
* @return number of bits sampled
**/
uint32_t SampleLF(bool printCfg, int sample_size)
{
	uint32_t ret = ReadLF(true, printCfg, sample_size);
	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()
{
	uint32_t ret = ReadLF(false, true, 0);
	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
	return ret;
}

/**
* acquisition of Cotag LF signal. Similar 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;
	uint16_t noise_counter = 0;
	while (!BUTTON_PRESS() && !usb_poll_validate_length() && (sample_counter < bufsize) && (noise_counter < (COTAG_T1<<1)) ) {
		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) {
					noise_counter++;
					continue;
				}
				noise_counter = 0;
				firsthigh = 1;
			}

			if ( !firstlow ){
				if (sample > COTAG_ZERO_THRESHOLD ) {
					noise_counter++;
					continue;
				}
				noise_counter=0;
				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
	9	#include "proxmark3.h"
	10	#include "apps.h"
	11	#include "util.h"
	12	#include "string.h"
31abe49f	13	#include "lfsampling.h"
e04475c4	14	#include "usb_cdc.h" // for usb_poll_validate_length
fc52fbd4	15	#include "fpgaloader.h"
10a8875c	16
2de26056	17	sample_config config = { 1, 8, 1, 95, 0, 0 } ;
31abe49f MHS	18
	19	void printConfig()
	20	{
e2012d1b	21	Dbprintf("LF Sampling config: ");
31abe49f MHS	22	Dbprintf(" [q] divisor: %d ", config.divisor);
	23	Dbprintf(" [b] bps: %d ", config.bits_per_sample);
	24	Dbprintf(" [d] decimation: %d ", config.decimation);
	25	Dbprintf(" [a] averaging: %d ", config.averaging);
	26	Dbprintf(" [t] trigger threshold: %d ", config.trigger_threshold);
2de26056	27	Dbprintf(" [s] samples to skip: %d ", config.samples_to_skip);
31abe49f MHS	28	}
	29
	30
	31	/**
	32	* Called from the USB-handler to set the sampling configuration
	33	* The sampling config is used for std reading and snooping.
	34	*
	35	* Other functions may read samples and ignore the sampling config,
	36	* such as functions to read the UID from a prox tag or similar.
	37	*
2de26056	38	* Values set to '0' implies no change (except for averaging, threshold, samples_to_skip)
31abe49f MHS	39	* @brief setSamplingConfig
	40	* @param sc
	41	*/
	42	void setSamplingConfig(sample_config *sc)
	43	{
	44	if(sc->divisor != 0) config.divisor = sc->divisor;
	45	if(sc->bits_per_sample!= 0) config.bits_per_sample= sc->bits_per_sample;
	46	if(sc->decimation!= 0) config.decimation= sc->decimation;
	47	if(sc->trigger_threshold != -1) config.trigger_threshold= sc->trigger_threshold;
2de26056	48	if(sc->samples_to_skip != -1) config.samples_to_skip = sc->samples_to_skip;
31abe49f MHS	49
	50	config.averaging= sc->averaging;
	51	if(config.bits_per_sample > 8) config.bits_per_sample = 8;
	52	if(config.decimation < 1) config.decimation = 1;
	53
	54	printConfig();
	55	}
	56
	57	sample_config* getSamplingConfig()
	58	{
	59	return &config;
	60	}
10a8875c	61
31abe49f MHS	62	typedef struct {
	63	uint8_t * buffer;
	64	uint32_t numbits;
	65	uint32_t position;
	66	} BitstreamOut;
	67
31abe49f MHS	68	/**
	69	* @brief Pushes bit onto the stream
	70	* @param stream
	71	* @param bit
	72	*/
10a8875c	73	void pushBit( BitstreamOut* stream, uint8_t bit)
31abe49f MHS	74	{
	75	int bytepos = stream->position >> 3; // divide by 8
	76	int bitpos = stream->position & 7;
	77	*(stream->buffer+bytepos) \|= (bit > 0) << (7 - bitpos);
	78	stream->position++;
	79	stream->numbits++;
	80	}
10a8875c	81
31abe49f MHS	82	/**
	83	* Setup the FPGA to listen for samples. This method downloads the FPGA bitstream
	84	* if not already loaded, sets divisor and starts up the antenna.
	85	* @param divisor : 1, 88> 255 or negative ==> 134.8 KHz
	86	* 0 or 95 ==> 125 KHz
	87	*
	88	**/
	89	void LFSetupFPGAForADC(int divisor, bool lf_field)
	90	{
	91	FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
	92	if ( (divisor == 1) \|\| (divisor < 0) \|\| (divisor > 255) )
	93	FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz
	94	else if (divisor == 0)
	95	FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
	96	else
	97	FpgaSendCommand(FPGA_CMD_SET_DIVISOR, divisor);
	98
	99	FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC \| (lf_field ? FPGA_LF_ADC_READER_FIELD : 0));
	100
	101	// Connect the A/D to the peak-detected low-frequency path.
	102	SetAdcMuxFor(GPIO_MUXSEL_LOPKD);
	103	// Give it a bit of time for the resonant antenna to settle.
	104	SpinDelay(50);
	105	// Now set up the SSC to get the ADC samples that are now streaming at us.
6a5d4e17	106	FpgaSetupSsc(FPGA_MAJOR_MODE_LF_ADC);
31abe49f MHS	107	}
31abe49f MHS	108
31abe49f MHS	109	/**
	110	* Does the sample acquisition. If threshold is specified, the actual sampling
	111	* is not commenced until the threshold has been reached.
	112	* This method implements decimation and quantization in order to
	113	* be able to provide longer sample traces.
	114	* Uses the following global settings:
	115	* @param decimation - how much should the signal be decimated. A decimation of N means we keep 1 in N samples, etc.
	116	* @param bits_per_sample - bits per sample. Max 8, min 1 bit per sample.
	117	* @param averaging If set to true, decimation will use averaging, so that if e.g. decimation is 3, the sample
	118	* value that will be used is the average value of the three samples.
	119	* @param trigger_threshold - a threshold. The sampling won't commence until this threshold has been reached. Set
	120	* to -1 to ignore threshold.
	121	* @param silent - is true, now outputs are made. If false, dbprints the status
	122	* @return the number of bits occupied by the samples.
	123	*/
2de26056	124	uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averaging, int trigger_threshold, bool silent, int bufsize, int cancel_after, int samples_to_skip)
31abe49f MHS	125	{
31abe49f MHS	126	//.
0644d5e3	127	uint8_t *dest = BigBuf_get_addr();
a37228c8	128	bufsize = (bufsize > 0 && bufsize < BigBuf_max_traceLen()) ? bufsize : BigBuf_max_traceLen();
0644d5e3	129
3cec7061	130	//memset(dest, 0, bufsize); //creates issues with cmdread (marshmellow)
31abe49f MHS	131
	132	if(bits_per_sample < 1) bits_per_sample = 1;
	133	if(bits_per_sample > 8) bits_per_sample = 8;
	134
	135	if(decimation < 1) decimation = 1;
	136
	137	// Use a bit stream to handle the output
	138	BitstreamOut data = { dest , 0, 0};
	139	int sample_counter = 0;
	140	uint8_t sample = 0;
	141	//If we want to do averaging
	142	uint32_t sample_sum =0 ;
	143	uint32_t sample_total_numbers =0 ;
	144	uint32_t sample_total_saved =0 ;
217cfb6b	145	uint32_t cancel_counter = 0;
2de26056	146	uint32_t samples_skipped = 0;
31abe49f	147
e04475c4	148	while(!BUTTON_PRESS() && !usb_poll_validate_length() ) {
31abe49f MHS	149	WDT_HIT();
	150	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
	151	AT91C_BASE_SSC->SSC_THR = 0x43;
	152	LED_D_ON();
	153	}
	154	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
	155	sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
	156	LED_D_OFF();
b29d55f2	157	// threshold either high or low values 128 = center 0. if trigger = 178
217cfb6b	158	if ((trigger_threshold > 0) && (sample < (trigger_threshold+128)) && (sample > (128-trigger_threshold))) { //
6469d550 I	159	if (cancel_after > 0) {
	160	cancel_counter++;
	161	if (cancel_after == cancel_counter) break;
	162	}
31abe49f	163	continue;
217cfb6b	164	}
31abe49f	165	trigger_threshold = 0;
2de26056	166	if (samples_to_skip > samples_skipped) {
	167	samples_skipped++;
	168	continue;
	169	}
31abe49f MHS	170	sample_total_numbers++;
	171
	172	if(averaging)
	173	{
	174	sample_sum += sample;
	175	}
	176	//Check decimation
	177	if(decimation > 1)
	178	{
	179	sample_counter++;
	180	if(sample_counter < decimation) continue;
	181	sample_counter = 0;
	182	}
	183	//Averaging
	184	if(averaging && decimation > 1) {
	185	sample = sample_sum / decimation;
	186	sample_sum =0;
	187	}
	188	//Store the sample
	189	sample_total_saved ++;
	190	if(bits_per_sample == 8){
	191	dest[sample_total_saved-1] = sample;
	192	data.numbits = sample_total_saved << 3;//Get the return value correct
	193	if(sample_total_saved >= bufsize) break;
	194	}
	195	else{
	196	pushBit(&data, sample & 0x80);
	197	if(bits_per_sample > 1) pushBit(&data, sample & 0x40);
	198	if(bits_per_sample > 2) pushBit(&data, sample & 0x20);
	199	if(bits_per_sample > 3) pushBit(&data, sample & 0x10);
	200	if(bits_per_sample > 4) pushBit(&data, sample & 0x08);
	201	if(bits_per_sample > 5) pushBit(&data, sample & 0x04);
	202	if(bits_per_sample > 6) pushBit(&data, sample & 0x02);
	203	//Not needed, 8bps is covered above
	204	//if(bits_per_sample > 7) pushBit(&data, sample & 0x01);
	205	if((data.numbits >> 3) +1 >= bufsize) break;
	206	}
	207	}
	208	}
	209
	210	if(!silent)
	211	{
	212	Dbprintf("Done, saved %d out of %d seen samples at %d bits/sample",sample_total_saved, sample_total_numbers,bits_per_sample);
	213	Dbprintf("buffer samples: %02x %02x %02x %02x %02x %02x %02x %02x ...",
	214	dest[0], dest[1], dest[2], dest[3], dest[4], dest[5], dest[6], dest[7]);
	215	}
	216	return data.numbits;
	217	}
	218	/**
	219	* @brief Does sample acquisition, ignoring the config values set in the sample_config.
	220	* This method is typically used by tag-specific readers who just wants to read the samples
	221	* the normal way
	222	* @param trigger_threshold
	223	* @param silent
	224	* @return number of bits sampled
	225	*/
	226	uint32_t DoAcquisition_default(int trigger_threshold, bool silent)
	227	{
2de26056	228	return DoAcquisition(1,8,0,trigger_threshold,silent,0,0,0);
31abe49f	229	}
b9957414	230	uint32_t DoAcquisition_config(bool silent, int sample_size)
31abe49f MHS	231	{
	232	return DoAcquisition(config.decimation
	233	,config.bits_per_sample
	234	,config.averaging
	235	,config.trigger_threshold
a37228c8	236	,silent
217cfb6b	237	,sample_size
2de26056	238	,0
2de26056	239	,config.samples_to_skip);
a37228c8	240	}
a37228c8	241
217cfb6b	242	uint32_t DoPartialAcquisition(int trigger_threshold, bool silent, int sample_size, int cancel_after) {
2de26056	243	return DoAcquisition(1,8,0,trigger_threshold,silent,sample_size,cancel_after,0);
31abe49f MHS	244	}
31abe49f MHS	245
b9957414	246	uint32_t ReadLF(bool activeField, bool silent, int sample_size)
31abe49f	247	{
1fbf8956	248	if (!silent) printConfig();
31abe49f MHS	249	LFSetupFPGAForADC(config.divisor, activeField);
31abe49f MHS	250	// Now call the acquisition routine
b9957414	251	return DoAcquisition_config(silent, sample_size);
31abe49f MHS	252	}
	253
	254	/**
	255	* Initializes the FPGA for reader-mode (field on), and acquires the samples.
	256	* @return number of bits sampled
	257	**/
b9957414	258	uint32_t SampleLF(bool printCfg, int sample_size)
31abe49f	259	{
b9957414	260	uint32_t ret = ReadLF(true, printCfg, sample_size);
e04475c4	261	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
e04475c4	262	return ret;
31abe49f MHS	263	}
	264	/**
	265	* Initializes the FPGA for snoop-mode (field off), and acquires the samples.
	266	* @return number of bits sampled
	267	**/
	268
	269	uint32_t SnoopLF()
	270	{
b9957414	271	uint32_t ret = ReadLF(false, true, 0);
e04475c4	272	FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
e04475c4	273	return ret;
31abe49f	274	}
7cfc777b	275
e04475c4	276	/**
2896e490	277	* acquisition of Cotag LF signal. Similar to other LF, since the Cotag has such long datarate RF/384
e04475c4	278	* and is Manchester?, we directly gather the manchester data into bigbuff
	279	**/
	280	#define COTAG_T1 384
	281	#define COTAG_T2 (COTAG_T1>>1)
	282	#define COTAG_ONE_THRESHOLD 128+30
	283	#define COTAG_ZERO_THRESHOLD 128-30
	284	#ifndef COTAG_BITS
	285	#define COTAG_BITS 264
	286	#endif
	287	void doCotagAcquisition(size_t sample_size) {
	288
	289	uint8_t *dest = BigBuf_get_addr();
	290	uint16_t bufsize = BigBuf_max_traceLen();
	291
	292	if ( bufsize > sample_size )
	293	bufsize = sample_size;
	294
	295	dest[0] = 0;
	296	uint8_t sample = 0, firsthigh = 0, firstlow = 0;
	297	uint16_t i = 0;
	298
	299	while (!BUTTON_PRESS() && !usb_poll_validate_length() && (i < bufsize) ) {
	300	WDT_HIT();
	301	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
	302	AT91C_BASE_SSC->SSC_THR = 0x43;
	303	LED_D_ON();
	304	}
	305
	306	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
	307	sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
	308	LED_D_OFF();
	309
	310	// find first peak
	311	if ( !firsthigh ) {
	312	if (sample < COTAG_ONE_THRESHOLD)
	313	continue;
	314	firsthigh = 1;
	315	}
	316	if ( !firstlow ){
	317	if (sample > COTAG_ZERO_THRESHOLD )
	318	continue;
	319	firstlow = 1;
	320	}
	321
	322	++i;
	323
	324	if ( sample > COTAG_ONE_THRESHOLD)
	325	dest[i] = 255;
	326	else if ( sample < COTAG_ZERO_THRESHOLD)
	327	dest[i] = 0;
	328	else
	329	dest[i] = dest[i-1];
	330	}
	331	}
	332	}
	333
	334	uint32_t doCotagAcquisitionManchester() {
	335
	336	uint8_t *dest = BigBuf_get_addr();
	337	uint16_t bufsize = BigBuf_max_traceLen();
	338
	339	if ( bufsize > COTAG_BITS )
	340	bufsize = COTAG_BITS;
	341
342	dest[0] = 0;
343	uint8_t sample = 0, firsthigh = 0, firstlow = 0;
344	uint16_t sample_counter = 0, period = 0;
345	uint8_t curr = 0, prev = 0;
217cfb6b	346	uint16_t noise_counter = 0;
cb593491	347	while (!BUTTON_PRESS() && !usb_poll_validate_length() && (sample_counter < bufsize) && (noise_counter < (COTAG_T1<<1)) ) {
e04475c4	348	WDT_HIT();
	349	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
	350	AT91C_BASE_SSC->SSC_THR = 0x43;
	351	LED_D_ON();
	352	}
	353
	354	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
	355	sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
	356	LED_D_OFF();
	357
	358	// find first peak
	359	if ( !firsthigh ) {
217cfb6b	360	if (sample < COTAG_ONE_THRESHOLD) {
217cfb6b	361	noise_counter++;
e04475c4	362	continue;
217cfb6b	363	}
217cfb6b	364	noise_counter = 0;
e04475c4	365	firsthigh = 1;
	366	}
	367
	368	if ( !firstlow ){
217cfb6b	369	if (sample > COTAG_ZERO_THRESHOLD ) {
217cfb6b	370	noise_counter++;
e04475c4	371	continue;
217cfb6b	372	}
217cfb6b	373	noise_counter=0;
e04475c4	374	firstlow = 1;
	375	}
	376
	377	// set sample 255, 0, or previous
	378	if ( sample > COTAG_ONE_THRESHOLD){
	379	prev = curr;
	380	curr = 1;
	381	}
	382	else if ( sample < COTAG_ZERO_THRESHOLD) {
	383	prev = curr;
	384	curr = 0;
	385	}
	386	else {
	387	curr = prev;
	388	}
	389
	390	// full T1 periods,
	391	if ( period > 0 ) {
	392	--period;
	393	continue;
	394	}
	395
	396	dest[sample_counter] = curr;
	397	++sample_counter;
	398	period = COTAG_T1;
	399	}
	400	}
	401	return sample_counter;
	402	}