/**
* 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)
{
//bigbuf, to hold the aquired raw data signal
uint8_t *dest = BigBuf_get_addr();
uint16_t bufsize = BigBuf_max_traceLen();
BigBuf_Clear_ext(false);
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;
}
}
}
void ReadPCF7931() {
uint8_t Blocks[8][17];
uint8_t tmpBlocks[4][16];
int i, j, ind, ind2, n;
int num_blocks = 0;
int max_blocks = 8;
int ident = 0;
int error = 0;
int tries = 0;
memset(Blocks, 0, 8*17*sizeof(uint8_t));
do {
memset(tmpBlocks, 0, 4*16*sizeof(uint8_t));
n = DemodPCF7931((uint8_t**)tmpBlocks);
if(!n)
error++;
if(error==10 && num_blocks == 0) {
Dbprintf("Error, no tag or bad tag");
return;
}
else if (tries==20 || error==10) {
Dbprintf("Error reading the tag");
Dbprintf("Here is the partial content");
goto end;
}
for(i=0; i<n; i++)
Dbprintf("(dbg) %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
tmpBlocks[i][0], tmpBlocks[i][1], tmpBlocks[i][2], tmpBlocks[i][3], tmpBlocks[i][4], tmpBlocks[i][5], tmpBlocks[i][6], tmpBlocks[i][7],
tmpBlocks[i][8], tmpBlocks[i][9], tmpBlocks[i][10], tmpBlocks[i][11], tmpBlocks[i][12], tmpBlocks[i][13], tmpBlocks[i][14], tmpBlocks[i][15]);
if(!ident) {
for(i=0; i<n; i++) {
if(IsBlock0PCF7931(tmpBlocks[i])) {
// Found block 0 ?
if(i < n-1 && IsBlock1PCF7931(tmpBlocks[i+1])) {
// Found block 1!
// \o/
ident = 1;
memcpy(Blocks[0], tmpBlocks[i], 16);
Blocks[0][ALLOC] = 1;
memcpy(Blocks[1], tmpBlocks[i+1], 16);
Blocks[1][ALLOC] = 1;
max_blocks = MAX((Blocks[1][14] & 0x7f), Blocks[1][15]) + 1;
// Debug print
Dbprintf("(dbg) Max blocks: %d", max_blocks);
num_blocks = 2;
// Handle following blocks
for(j=i+2, ind2=2; j!=i; j++, ind2++, num_blocks++) {
if(j==n) j=0;
if(j==i) break;
memcpy(Blocks[ind2], tmpBlocks[j], 16);
Blocks[ind2][ALLOC] = 1;
}
break;
}
}
}
}
else {
for(i=0; i<n; i++) { // Look for identical block in known blocks
if(memcmp(tmpBlocks[i], "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16)) { // Block is not full of 00
for(j=0; j<max_blocks; j++) {
if(Blocks[j][ALLOC] == 1 && !memcmp(tmpBlocks[i], Blocks[j], 16)) {
// Found an identical block
for(ind=i-1,ind2=j-1; ind >= 0; ind--,ind2--) {
if(ind2 < 0)
ind2 = max_blocks;
if(!Blocks[ind2][ALLOC]) { // Block ind2 not already found
// Dbprintf("Tmp %d -> Block %d", ind, ind2);
memcpy(Blocks[ind2], tmpBlocks[ind], 16);
Blocks[ind2][ALLOC] = 1;
num_blocks++;
if(num_blocks == max_blocks) goto end;
}
}
for(ind=i+1,ind2=j+1; ind < n; ind++,ind2++) {
if(ind2 > max_blocks)
ind2 = 0;
if(!Blocks[ind2][ALLOC]) { // Block ind2 not already found
// Dbprintf("Tmp %d -> Block %d", ind, ind2);
memcpy(Blocks[ind2], tmpBlocks[ind], 16);
Blocks[ind2][ALLOC] = 1;
num_blocks++;
if(num_blocks == max_blocks) goto end;
}
}
}
}
}
}
}
tries++;
if (BUTTON_PRESS()) return;
} while (num_blocks != max_blocks);
end:
Dbprintf("-----------------------------------------");
Dbprintf("Memory content:");
Dbprintf("-----------------------------------------");
for(i=0; i<max_blocks; i++) {
if(Blocks[i][ALLOC]==1)
Dbprintf("%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
Blocks[i][0], Blocks[i][1], Blocks[i][2], Blocks[i][3], Blocks[i][4], Blocks[i][5], Blocks[i][6], Blocks[i][7],
Blocks[i][8], Blocks[i][9], Blocks[i][10], Blocks[i][11], Blocks[i][12], Blocks[i][13], Blocks[i][14], Blocks[i][15]);
else
Dbprintf("<missing block %d>", i);
}
Dbprintf("-----------------------------------------");
cmd_send(CMD_ACK,0,0,0,0,0);
}