[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"

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

void printConfig()
{
	Dbprintf("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);
}


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

	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();
}


/**
 * 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)
{
	//.
	uint8_t *dest = BigBuf_get_addr();
    int bufsize = BigBuf_max_traceLen();

	memset(dest, 0, bufsize);

	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()) {
		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;
		
			//if (trigger_threshold > 0 && sample < 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);
}
uint32_t DoAcquisition_config( bool silent)
{
	return DoAcquisition(config.decimation
				  ,config.bits_per_sample
				  ,config.averaging
				  ,config.trigger_threshold
				  ,silent);
}

uint32_t ReadLF(bool activeField, bool silent)
{
	if (!silent) printConfig();
	LFSetupFPGAForADC(config.divisor, activeField);
	// Now call the acquisition routine
	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)
{
	return ReadLF(true, printCfg);
}
/**
* Initializes the FPGA for snoop-mode (field off), and acquires the samples.
* @return number of bits sampled
**/

uint32_t SnoopLF()
{
	return ReadLF(false, true);
}
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"
	13
	14	#include "lfsampling.h"
10a8875c	15
0cd2a41a	16	sample_config config = { 1, 8, 1, 95, 0 } ;
31abe49f MHS	17
	18	void printConfig()
	19	{
	20	Dbprintf("Sampling config: ");
	21	Dbprintf(" [q] divisor: %d ", config.divisor);
	22	Dbprintf(" [b] bps: %d ", config.bits_per_sample);
	23	Dbprintf(" [d] decimation: %d ", config.decimation);
	24	Dbprintf(" [a] averaging: %d ", config.averaging);
	25	Dbprintf(" [t] trigger threshold: %d ", config.trigger_threshold);
	26	}
	27
	28
	29	/**
	30	* Called from the USB-handler to set the sampling configuration
	31	* The sampling config is used for std reading and snooping.
	32	*
	33	* Other functions may read samples and ignore the sampling config,
	34	* such as functions to read the UID from a prox tag or similar.
	35	*
	36	* Values set to '0' implies no change (except for averaging)
	37	* @brief setSamplingConfig
	38	* @param sc
	39	*/
	40	void setSamplingConfig(sample_config *sc)
	41	{
	42	if(sc->divisor != 0) config.divisor = sc->divisor;
	43	if(sc->bits_per_sample!= 0) config.bits_per_sample= sc->bits_per_sample;
	44	if(sc->decimation!= 0) config.decimation= sc->decimation;
	45	if(sc->trigger_threshold != -1) config.trigger_threshold= sc->trigger_threshold;
	46
	47	config.averaging= sc->averaging;
	48	if(config.bits_per_sample > 8) config.bits_per_sample = 8;
	49	if(config.decimation < 1) config.decimation = 1;
	50
	51	printConfig();
	52	}
	53
	54	sample_config* getSamplingConfig()
	55	{
	56	return &config;
	57	}
10a8875c	58
31abe49f MHS	59	typedef struct {
	60	uint8_t * buffer;
	61	uint32_t numbits;
	62	uint32_t position;
	63	} BitstreamOut;
	64
31abe49f MHS	65	/**
	66	* @brief Pushes bit onto the stream
	67	* @param stream
	68	* @param bit
	69	*/
10a8875c	70	void pushBit( BitstreamOut* stream, uint8_t bit)
31abe49f MHS	71	{
	72	int bytepos = stream->position >> 3; // divide by 8
	73	int bitpos = stream->position & 7;
	74	*(stream->buffer+bytepos) \|= (bit > 0) << (7 - bitpos);
	75	stream->position++;
	76	stream->numbits++;
	77	}
10a8875c	78
31abe49f MHS	79	/**
	80	* Setup the FPGA to listen for samples. This method downloads the FPGA bitstream
	81	* if not already loaded, sets divisor and starts up the antenna.
	82	* @param divisor : 1, 88> 255 or negative ==> 134.8 KHz
	83	* 0 or 95 ==> 125 KHz
	84	*
	85	**/
	86	void LFSetupFPGAForADC(int divisor, bool lf_field)
	87	{
	88	FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
	89	if ( (divisor == 1) \|\| (divisor < 0) \|\| (divisor > 255) )
	90	FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz
	91	else if (divisor == 0)
	92	FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
	93	else
	94	FpgaSendCommand(FPGA_CMD_SET_DIVISOR, divisor);
	95
	96	FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_ADC \| (lf_field ? FPGA_LF_ADC_READER_FIELD : 0));
	97
	98	// Connect the A/D to the peak-detected low-frequency path.
	99	SetAdcMuxFor(GPIO_MUXSEL_LOPKD);
	100	// Give it a bit of time for the resonant antenna to settle.
	101	SpinDelay(50);
	102	// Now set up the SSC to get the ADC samples that are now streaming at us.
	103	FpgaSetupSsc();
	104	}
	105
	106
	107	/**
	108	* Does the sample acquisition. If threshold is specified, the actual sampling
	109	* is not commenced until the threshold has been reached.
	110	* This method implements decimation and quantization in order to
	111	* be able to provide longer sample traces.
	112	* Uses the following global settings:
	113	* @param decimation - how much should the signal be decimated. A decimation of N means we keep 1 in N samples, etc.
	114	* @param bits_per_sample - bits per sample. Max 8, min 1 bit per sample.
	115	* @param averaging If set to true, decimation will use averaging, so that if e.g. decimation is 3, the sample
	116	* value that will be used is the average value of the three samples.
	117	* @param trigger_threshold - a threshold. The sampling won't commence until this threshold has been reached. Set
	118	* to -1 to ignore threshold.
	119	* @param silent - is true, now outputs are made. If false, dbprints the status
	120	* @return the number of bits occupied by the samples.
	121	*/
b29d55f2	122	uint32_t DoAcquisition(uint8_t decimation, uint32_t bits_per_sample, bool averaging, int trigger_threshold, bool silent)
31abe49f MHS	123	{
31abe49f MHS	124	//.
0644d5e3 MHS	125	uint8_t *dest = BigBuf_get_addr();
	126	int bufsize = BigBuf_max_traceLen();
	127
31abe49f MHS	128	memset(dest, 0, bufsize);
	129
	130	if(bits_per_sample < 1) bits_per_sample = 1;
	131	if(bits_per_sample > 8) bits_per_sample = 8;
	132
	133	if(decimation < 1) decimation = 1;
	134
	135	// Use a bit stream to handle the output
	136	BitstreamOut data = { dest , 0, 0};
	137	int sample_counter = 0;
	138	uint8_t sample = 0;
	139	//If we want to do averaging
	140	uint32_t sample_sum =0 ;
	141	uint32_t sample_total_numbers =0 ;
	142	uint32_t sample_total_saved =0 ;
	143
	144	while(!BUTTON_PRESS()) {
	145	WDT_HIT();
	146	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_TXRDY) {
	147	AT91C_BASE_SSC->SSC_THR = 0x43;
	148	LED_D_ON();
	149	}
	150	if (AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY) {
	151	sample = (uint8_t)AT91C_BASE_SSC->SSC_RHR;
	152	LED_D_OFF();
b29d55f2	153	// threshold either high or low values 128 = center 0. if trigger = 178
b29d55f2	154	if ((trigger_threshold > 0) && (sample < (trigger_threshold+128)) && (sample > (128-trigger_threshold))) //
31abe49f	155	continue;
b29d55f2	156
	157	//if (trigger_threshold > 0 && sample < trigger_threshold) //
	158	//continue;
31abe49f MHS	159
	160	trigger_threshold = 0;
	161	sample_total_numbers++;
	162
	163	if(averaging)
	164	{
	165	sample_sum += sample;
	166	}
	167	//Check decimation
	168	if(decimation > 1)
	169	{
	170	sample_counter++;
	171	if(sample_counter < decimation) continue;
	172	sample_counter = 0;
	173	}
	174	//Averaging
	175	if(averaging && decimation > 1) {
	176	sample = sample_sum / decimation;
	177	sample_sum =0;
	178	}
	179	//Store the sample
	180	sample_total_saved ++;
	181	if(bits_per_sample == 8){
	182	dest[sample_total_saved-1] = sample;
	183	data.numbits = sample_total_saved << 3;//Get the return value correct
	184	if(sample_total_saved >= bufsize) break;
	185	}
	186	else{
	187	pushBit(&data, sample & 0x80);
	188	if(bits_per_sample > 1) pushBit(&data, sample & 0x40);
	189	if(bits_per_sample > 2) pushBit(&data, sample & 0x20);
	190	if(bits_per_sample > 3) pushBit(&data, sample & 0x10);
	191	if(bits_per_sample > 4) pushBit(&data, sample & 0x08);
	192	if(bits_per_sample > 5) pushBit(&data, sample & 0x04);
	193	if(bits_per_sample > 6) pushBit(&data, sample & 0x02);
	194	//Not needed, 8bps is covered above
	195	//if(bits_per_sample > 7) pushBit(&data, sample & 0x01);
	196	if((data.numbits >> 3) +1 >= bufsize) break;
	197	}
	198	}
	199	}
	200
	201	if(!silent)
	202	{
	203	Dbprintf("Done, saved %d out of %d seen samples at %d bits/sample",sample_total_saved, sample_total_numbers,bits_per_sample);
	204	Dbprintf("buffer samples: %02x %02x %02x %02x %02x %02x %02x %02x ...",
	205	dest[0], dest[1], dest[2], dest[3], dest[4], dest[5], dest[6], dest[7]);
	206	}
	207	return data.numbits;
	208	}
	209	/**
	210	* @brief Does sample acquisition, ignoring the config values set in the sample_config.
	211	* This method is typically used by tag-specific readers who just wants to read the samples
	212	* the normal way
	213	* @param trigger_threshold
	214	* @param silent
	215	* @return number of bits sampled
	216	*/
	217	uint32_t DoAcquisition_default(int trigger_threshold, bool silent)
	218	{
	219	return DoAcquisition(1,8,0,trigger_threshold,silent);
	220	}
	221	uint32_t DoAcquisition_config( bool silent)
	222	{
223	return DoAcquisition(config.decimation
224	,config.bits_per_sample
225	,config.averaging
226	,config.trigger_threshold
227	,silent);
228	}
229
1fbf8956	230	uint32_t ReadLF(bool activeField, bool silent)
31abe49f	231	{
1fbf8956	232	if (!silent) printConfig();
31abe49f MHS	233	LFSetupFPGAForADC(config.divisor, activeField);
31abe49f MHS	234	// Now call the acquisition routine
1fbf8956	235	return DoAcquisition_config(silent);
31abe49f MHS	236	}
	237
	238	/**
	239	* Initializes the FPGA for reader-mode (field on), and acquires the samples.
	240	* @return number of bits sampled
	241	**/
1fbf8956	242	uint32_t SampleLF(bool printCfg)
31abe49f	243	{
1fbf8956	244	return ReadLF(true, printCfg);
31abe49f MHS	245	}
	246	/**
	247	* Initializes the FPGA for snoop-mode (field off), and acquires the samples.
	248	* @return number of bits sampled
	249	**/
	250
	251	uint32_t SnoopLF()
	252	{
1fbf8956	253	return ReadLF(false, true);
31abe49f	254	}