/* TestTwinPeaks.ino Bob Larkin 26 Feb 2022 1 * Tests the AlignLR class for finding the relative * time order of the Codec ADC L and R channels, and then * corrects these offsets. * * This applies a common analog square wave signal to the L and R inputs. * The cross-correlation between the channels is found for * the different offsets, showing the identical output. * * The outputs of the AlignLR object is then corrected, if necessary, * by delaying either the L or R channel. * * This test allows the analog signal to come from either the Codec * DAC or from a digital I/O pin on the Teensy. * */ // Beta rev 12 Mar 2022: Added normalized measures and removed threshold. Moved // the L-R alignment to setup(). #include "Audio.h" #include "OpenAudio_ArduinoLibrary.h" // ******* MINI CONTROL PANEL ******* // // Pick one, based on the analog signal source harware being used: //#define SIGNAL_HARDWARE TP_SIGNAL_CODEC #define SIGNAL_HARDWARE TP_SIGNAL_IO_PIN // // Show the Teensy pin used for both Codec and I/O pin signal source methods #define PIN_FOR_TP 2 // // Set threshold as needed. Examine 3 output data around update #15 // and use about half of maximum positive value. // #define TP_THRESHOLD 0.001f <<<< No Longer Used // // End Control Panel const float sample_rate_Hz = 44100.0f; const int audio_block_samples = 128; AudioSettings_F32 audio_settings(sample_rate_Hz, audio_block_samples); TPinfo* pData; uint32_t timeSquareWave = 0; // Switch every twoPeriods microseconds uint32_t twoPeriods; AudioInputI2S_F32 i2sIn; // BEWARE _ -- The SIGNAL_HARDWARE==TP_SIGNAL_CODEC is likely to be removed and // then the constructtion of the object will be *ONLY* the simple cases // of TwinPeak(audio_settings) or just TwinPeak // Pin or Codec Pin, Invert AudioAlignLR_F32 TwinPeak(SIGNAL_HARDWARE, PIN_FOR_TP, false, audio_settings); AudioOutputI2S_F32 i2sOut; #ifdef PRINT_OUTPUT_DATA AudioRecordQueue_F32 q1; AudioRecordQueue_F32 q2; #endif AudioControlSGTL5000 codec; AudioConnection_F32 connection1(i2sIn, 0, TwinPeak, 0); AudioConnection_F32 connection2(i2sIn, 1, TwinPeak, 1); #if SIGNAL_HARDWARE==TP_SIGNAL_CODEC // Not realistic for a radio but useful for testing AudioConnection_F32 connection3(TwinPeak, 2, i2sOut, 1); // DAC R #endif #if SIGNAL_HARDWARE==TP_SIGNAL_IO_PIN // Not realistic for a radio but useful for testing AudioConnection_F32 connection4(TwinPeak, 1, i2sOut, 1); // DAC R #endif AudioConnection_F32 connection5(TwinPeak, 0, i2sOut, 0); // DAC L // For test, send to queue. For real, send to receiver. #ifdef PRINT_OUTPUT_DATA AudioConnection_F32 connection6(TwinPeak, 0, q1, 0); AudioConnection_F32 connection7(TwinPeak, 1, q2, 0); #endif void setup(void) { uint32_t tMillis = millis(); AudioMemory_F32(50, audio_settings); Serial.begin(100); // Any rate delay(500); Serial.println("Twin Peaks L-R Synchronizer Test"); codec.inputSelect(AUDIO_INPUT_LINEIN); codec.enable(); // This needs to preceed TwinPeak setup #if SIGNAL_HARDWARE==TP_SIGNAL_CODEC Serial.println("Using SGTL5000 Codec output for cross-correlation test signal."); #endif #if SIGNAL_HARDWARE==TP_SIGNAL_IO_PIN pinMode (PIN_FOR_TP, OUTPUT); // Digital output pin Serial.println("Using I/O pin for cross-correlation test signal."); #endif //TwinPeak.setThreshold(TP_THRESHOLD); Not used TwinPeak.stateAlignLR(TP_MEASURE); // Comes up TP_IDLE #if SIGNAL_HARDWARE==TP_SIGNAL_IO_PIN twoPeriods = (uint32_t)(0.5f + (2000000.0f / sample_rate_Hz)); // Note that for this hardware, the INO is 100% in charge of the PIN_FOR_TP pData = TwinPeak.read(); // Base data to check error while (pData->TPerror < 0 && millis()-tMillis < 2000) // with timeout { if(micros()-timeSquareWave >= twoPeriods && pData->TPstate==TP_MEASURE) { static uint16_t squareWave = 0; timeSquareWave = micros(); squareWave = squareWave^1; digitalWrite(PIN_FOR_TP, squareWave); } pData = TwinPeak.read(); } // The update has moved from Measure to Run. Ground the PIN_FOR_TP //TwinPeak.stateAlignLR(TP_RUN); // TP is done, not TP_MEASURE digitalWrite(PIN_FOR_TP, 0); // Set pin to zero Serial.println(""); Serial.println("Update ------------ Outputs ------------"); Serial.println("Number xNorm -1 0 1 Shift Error State");// Column headings Serial.print(pData->nMeas); Serial.print(", "); Serial.print(pData->xNorm, 6); Serial.print(", "); Serial.print(pData->xcVal[3], 6); Serial.print(", "); Serial.print(pData->xcVal[0], 6); Serial.print(", "); Serial.print(pData->xcVal[1], 6); Serial.print(", "); Serial.print(pData->neededShift); Serial.print(", "); Serial.print(pData->TPerror); Serial.print(", "); Serial.println(pData->TPstate); // You can see the injected signal level by the printed variable, pData->xNorm // It is the sum of the 4 cross-correlation numbers and if it is below 0.0001 the // measurement is getting noisy and un-reliable. Raise the injected signal level // to solve the problem. #endif } void loop(void) { }