fixing iso14443b (issue #103):

- fix: IQ demodulator (FPGA)
- fix: approximately align reader signal delay to tag response delay (FPGA)
- fix: remove deprecated RSSI calculation to improve decoder speed (iso14443b.c)
- fix: better approximation of signal amplitude to avoid false carrier detection (iso14443b.c)
- fix: remove initial power off in iso14443b raw command (iso14443b.c)
- add: enable tracing for iso14443b raw command (iso14443b.c)
- fix: client crashed when checking CRC for incomplete responses (iso14433b.c)
- speeding up snoop to avoid circular buffer overflow
- added some comments for better documentation
- rename functions (iso14443 -> iso14443b)
- remove unused code in hi_read_rx_xcorr.v

armsrc/appmain.c

@@ -263,7 +263,7 @@ void SimulateTagHfListen(void)
 	// We're using this mode just so that I can test it out; the simulated
 	// tag mode would work just as well and be simpler.
 	FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
-	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ | FPGA_HF_READER_RX_XCORR_SNOOP);
+	FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_SNOOP);
 
 	// We need to listen to the high-frequency, peak-detected path.
 	SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
@@ -783,19 +783,19 @@ void UsbPacketReceived(uint8_t *packet, int len)
 
 #ifdef WITH_ISO14443b
 		case CMD_ACQUIRE_RAW_ADC_SAMPLES_ISO_14443:
-			AcquireRawAdcSamplesIso14443(c->arg[0]);
+			AcquireRawAdcSamplesIso14443b(c->arg[0]);
 			break;
 		case CMD_READ_SRI512_TAG:
-			ReadSTMemoryIso14443(0x0F);
+			ReadSTMemoryIso14443b(0x0F);
 			break;
 		case CMD_READ_SRIX4K_TAG:
-			ReadSTMemoryIso14443(0x7F);
+			ReadSTMemoryIso14443b(0x7F);
 			break;
 		case CMD_SNOOP_ISO_14443:
-			SnoopIso14443();
+			SnoopIso14443b();
 			break;
 		case CMD_SIMULATE_TAG_ISO_14443:
-			SimulateIso14443Tag();
+			SimulateIso14443bTag();
 			break;
 		case CMD_ISO_14443B_COMMAND:
 			SendRawCommand14443B(c->arg[0],c->arg[1],c->arg[2],c->d.asBytes);