+
+/**
+* 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+40 // 40 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;
+
+ uint16_t i = 0;
+ bool startFound = false;
+ bool highFound = false;
+ uint8_t curSample = 0;
+ uint8_t lastSample = 0;
+ uint16_t skipCnt = 0;
+ while(!BUTTON_PRESS() && skipCnt<1000) {
+ 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) {
+ 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 first high samples begin to change
+ if (startFound || curSample < T55xx_READ_UPPER_THRESHOLD-T55xx_READ_TOL){
+ // if just found start - recover last sample
+ if (!startFound) {
+ dest[i++] = lastSample;
+ startFound = true;
+ }
+ // collect samples
+ dest[i++] = curSample;
+ if (i >= bufsize-1) break;
+ }
+ }
+ }
+}