comparison examples/04-Audio/bucket-brigade-chorus/render.cpp @ 464:8fcfbfb32aa0 prerelease

Examples reorder with subdirectories. Added header to each project. Moved Doxygen to bottom of render.cpp.

+/*
+ ____  _____ _        _    
+| __ )| ____| |      / \   
+|  _ \|  _| | |     / _ \  
+| |_) | |___| |___ / ___ \ 
+|____/|_____|_____/_/   \_\
+
+The platform for ultra-low latency audio and sensor processing
+
+http://bela.io
+
+A project of the Augmented Instruments Laboratory within the
+Centre for Digital Music at Queen Mary University of London.
+http://www.eecs.qmul.ac.uk/~andrewm
+
+(c) 2016 Augmented Instruments Laboratory: Andrew McPherson,
+	Astrid Bin, Liam Donovan, Christian Heinrichs, Robert Jack,
+	Giulio Moro, Laurel Pardue, Victor Zappi. All rights reserved.
+
+The Bela software is distributed under the GNU Lesser General Public License
+(LGPL 3.0), available here: https://www.gnu.org/licenses/lgpl-3.0.txt
+*/
+
+
+#include <Bela.h> 
+#include <Scope.h>
+#include <cmath>
+
+float gPhase1, gPhase2;
+float gFrequency1, gFrequency2;
+float gInverseSampleRate;
+
+// initialise_render() is called once before the audio rendering starts.
+// Use it to perform any initialisation and allocation which is dependent
+// on the period size or sample rate.
+//
+// userData holds an opaque pointer to a data structure that was passed
+// in from the call to initAudio().
+//
+// Return true on success; returning false halts the program.
+#include <I2c_Codec.h>
+#include <PRU.h>
+extern I2c_Codec *gAudioCodec;
+extern PRU *gPRU;
+float D=5264;
+#define delayLength 256
+float delay[delayLength];
+int writePointer=0;
+int readPointer=writePointer+1;
+AuxiliaryTask updatePll;
+
+void updatePllFunction(){
+//	gPRU->setGPIOTestPin();
+	static int count = 0;
+	while(!gShouldStop){
+		gAudioCodec->setPllD(D);
+		count++;
+		if((count&4095)==0)
+			printf("sampling rate: %f\n",gAudioCodec->getAudioSamplingRate());
+		usleep(100);
+	}
+//	gPRU->clearGPIOTestPin();
+}
+
+bool setup(BelaContext *context, void *userData)
+{
+	gInverseSampleRate = 1.0/context->audioSampleRate;
+	
+	gPhase1 = 0.0;
+	gPhase2 = 0.0;
+	
+	gFrequency1 = 200.0;
+	gFrequency2 = 201.0;
+	updatePll=Bela_createAuxiliaryTask(&updatePllFunction, 91, "update PLL");
+	for(int n=0; n<delayLength; n++){
+		delay[n]=0;
+	}
+	return true; 
+}
+
+// render() is called regularly at the highest priority by the audio engine.
+// Input and output are given from the audio hardware and the other
+// ADCs and DACs (if available). If only audio is available, numMatrixFrames
+// will be 0.
+
+void render(BelaContext *context, void *userData)
+{
+//	printf("here\n");
+	static bool init = false;
+	if(init == false){
+		Bela_scheduleAuxiliaryTask(updatePll);
+//		gAudioCodec->setPllP(2);
+//		gAudioCodec->setPllR();
+//		gAudioCodec->setAudioSamplingRate(43600);
+//		printf("samplingRate: %f, k: %f\n", gAudioCodec->getAudioSamplingRate(), gAudioCodec->getPllK());
+		init = true;
+	}
+	static int count=0;
+	static float lfoPhase=0;
+	static float feedback=0;
+	int updateRate=1;
+	if((count&(updateRate-1))==0){
+		float amplitude = 8000;
+		float rate = 2;
+		lfoPhase+=rate*2*M_PI*updateRate*context->analogFrames/context->audioSampleRate;
+		D=amplitude+amplitude*sinf(lfoPhase);
+		if((count&255)==0){
+//			rt_printf("frequency: %f\n", gAudioCodec->getAudioSamplingRate());
+//			rt_printf("D: %.0f\n", D);
+//			rt_printf("rate: %f\n", rate);
+//			rt_printf("amplitude: %.3f\n", amplitude);
+//			rt_printf("feedback: %.3f\n\n", feedback);
+		}
+	}
+	count++;
+
+	for(unsigned int n = 0; n < context->audioFrames; n++) {
+		feedback = 0.4;
+		float input = audioRead(context, n, 0) + audioRead(context, n, 1);
+	    delay[writePointer++] = input + delay[readPointer]*feedback;
+	    float output = (input + 0.9*delay[readPointer++] ) * 0.5;
+		audioWrite(context, n, 0, output);
+		audioWrite(context, n, 1, output);
+		if(writePointer>=delayLength)
+			writePointer-=delayLength;
+		if(readPointer>=delayLength)
+			readPointer-=delayLength;
+
+		gPhase1 += 2.0 * M_PI * gFrequency1 * gInverseSampleRate;
+	    gPhase2 += 2.0 * M_PI * gFrequency2 * gInverseSampleRate;
+		if(gPhase1 > 2.0 * M_PI)
+			gPhase1 -= 2.0 * M_PI;
+		if(gPhase2 > 2.0 * M_PI)
+			gPhase2 -= 2.0 * M_PI;
+	}
+}
+
+// cleanup_render() is called once at the end, after the audio has stopped.
+// Release any resources that were allocated in initialise_render().
+
+void cleanup(BelaContext *context, void *userData)
+{
+    
+}