giuliomoro@98: #include <BeagleRT.h> 
giuliomoro@98: #include <Scope.h>
giuliomoro@98: #include <cmath>
giuliomoro@98: #include <Utilities.h>
giuliomoro@98: 
giuliomoro@98: float gPhase1, gPhase2;
giuliomoro@98: float gFrequency1, gFrequency2;
giuliomoro@98: float gInverseSampleRate;
giuliomoro@98: 
giuliomoro@98: // initialise_render() is called once before the audio rendering starts.
giuliomoro@98: // Use it to perform any initialisation and allocation which is dependent
giuliomoro@98: // on the period size or sample rate.
giuliomoro@98: //
giuliomoro@98: // userData holds an opaque pointer to a data structure that was passed
giuliomoro@98: // in from the call to initAudio().
giuliomoro@98: //
giuliomoro@98: // Return true on success; returning false halts the program.
giuliomoro@98: #include <I2c_Codec.h>
giuliomoro@98: #include <PRU.h>
giuliomoro@98: extern I2c_Codec *gAudioCodec;
giuliomoro@98: extern PRU *gPRU;
giuliomoro@98: float D=5264;
giuliomoro@183: #define delayLength 256
giuliomoro@98: float delay[delayLength];
giuliomoro@98: int writePointer=0;
giuliomoro@98: int readPointer=writePointer+1;
giuliomoro@98: AuxiliaryTask updatePll;
giuliomoro@98: 
giuliomoro@98: void updatePllFunction(){
giuliomoro@183: //	gPRU->setGPIOTestPin();
giuliomoro@183: 	static int count = 0;
giuliomoro@183: 	while(!gShouldStop){
giuliomoro@183: 		gAudioCodec->setPllD(D);
giuliomoro@183: 		count++;
giuliomoro@183: 		if((count&4095)==0)
giuliomoro@183: 			printf("sampling rate: %f\n",gAudioCodec->getAudioSamplingRate());
giuliomoro@183: 		usleep(100);
giuliomoro@183: 	}
giuliomoro@183: //	gPRU->clearGPIOTestPin();
giuliomoro@98: }
giuliomoro@98: 
giuliomoro@98: bool setup(BeagleRTContext *context, void *userData)
giuliomoro@98: {
giuliomoro@98: 	gInverseSampleRate = 1.0/context->audioSampleRate;
giuliomoro@98: 	
giuliomoro@98: 	gPhase1 = 0.0;
giuliomoro@98: 	gPhase2 = 0.0;
giuliomoro@98: 	
giuliomoro@98: 	gFrequency1 = 200.0;
giuliomoro@98: 	gFrequency2 = 201.0;
giuliomoro@183: 	updatePll=BeagleRT_createAuxiliaryTask(&updatePllFunction, 91, "update PLL");
giuliomoro@98: 	for(int n=0; n<delayLength; n++){
giuliomoro@98: 		delay[n]=0;
giuliomoro@98: 	}
giuliomoro@98: 	return true; 
giuliomoro@98: }
giuliomoro@98: 
giuliomoro@98: // render() is called regularly at the highest priority by the audio engine.
giuliomoro@98: // Input and output are given from the audio hardware and the other
giuliomoro@98: // ADCs and DACs (if available). If only audio is available, numMatrixFrames
giuliomoro@98: // will be 0.
giuliomoro@98: 
giuliomoro@98: void render(BeagleRTContext *context, void *userData)
giuliomoro@98: {
giuliomoro@183: //	printf("here\n");
giuliomoro@183: 	static bool init = false;
giuliomoro@183: 	if(init == false){
giuliomoro@183: 		BeagleRT_scheduleAuxiliaryTask(updatePll);
giuliomoro@183: //		gAudioCodec->setPllP(2);
giuliomoro@183: //		gAudioCodec->setPllR();
giuliomoro@183: //		gAudioCodec->setAudioSamplingRate(43600);
giuliomoro@183: //		printf("samplingRate: %f, k: %f\n", gAudioCodec->getAudioSamplingRate(), gAudioCodec->getPllK());
giuliomoro@183: 		init = true;
giuliomoro@183: 	}
giuliomoro@98: 	static int count=0;
giuliomoro@98: 	static float lfoPhase=0;
giuliomoro@98: 	static float feedback=0;
giuliomoro@183: 	int updateRate=1;
giuliomoro@183: 	if((count&(updateRate-1))==0){
giuliomoro@183: 		float amplitude = 8000;
giuliomoro@183: 		float rate = 2;
giuliomoro@98: 		lfoPhase+=rate*2*M_PI*updateRate*context->analogFrames/context->audioSampleRate;
giuliomoro@98: 		D=amplitude+amplitude*sinf(lfoPhase);
giuliomoro@98: 		if((count&255)==0){
giuliomoro@183: //			rt_printf("frequency: %f\n", gAudioCodec->getAudioSamplingRate());
giuliomoro@183: //			rt_printf("D: %.0f\n", D);
giuliomoro@183: //			rt_printf("rate: %f\n", rate);
giuliomoro@183: //			rt_printf("amplitude: %.3f\n", amplitude);
giuliomoro@183: //			rt_printf("feedback: %.3f\n\n", feedback);
giuliomoro@98: 		}
giuliomoro@98: 	}
giuliomoro@98: 	count++;
giuliomoro@98: 
giuliomoro@98: 	for(unsigned int n = 0; n < context->audioFrames; n++) {
giuliomoro@183: 		feedback = 0.4;
giuliomoro@183: 		float input = audioReadFrame(context, n, 0) + audioReadFrame(context, n, 1);
giuliomoro@183: 	    delay[writePointer++] = input + delay[readPointer]*feedback;
giuliomoro@183: 	    float output = (input + 0.9*delay[readPointer++] ) * 0.5;
giuliomoro@183: 		audioWriteFrame(context, n, 0, output);
giuliomoro@183: 		audioWriteFrame(context, n, 1, output);
giuliomoro@98: 		if(writePointer>=delayLength)
giuliomoro@98: 			writePointer-=delayLength;
giuliomoro@98: 		if(readPointer>=delayLength)
giuliomoro@98: 			readPointer-=delayLength;
giuliomoro@98: 
giuliomoro@98: 		gPhase1 += 2.0 * M_PI * gFrequency1 * gInverseSampleRate;
giuliomoro@98: 	    gPhase2 += 2.0 * M_PI * gFrequency2 * gInverseSampleRate;
giuliomoro@98: 		if(gPhase1 > 2.0 * M_PI)
giuliomoro@98: 			gPhase1 -= 2.0 * M_PI;
giuliomoro@98: 		if(gPhase2 > 2.0 * M_PI)
giuliomoro@98: 			gPhase2 -= 2.0 * M_PI;
giuliomoro@98: 	}
giuliomoro@98: }
giuliomoro@98: 
giuliomoro@98: // cleanup_render() is called once at the end, after the audio has stopped.
giuliomoro@98: // Release any resources that were allocated in initialise_render().
giuliomoro@98: 
giuliomoro@98: void cleanup(BeagleRTContext *context, void *userData)
giuliomoro@98: {
giuliomoro@98:     
giuliomoro@98: }