l@273: #include <BeagleRT.h>
l@273: #include <Scope.h>
l@273: #include <cmath>
l@273: 
l@273: // set the frequency of the oscillators
l@273: float gFrequency = 110.0;
l@273: float gPhase;
l@273: float gInverseSampleRate;
l@273: 
l@273: // instantiate the scope
l@273: Scope scope;
l@273: 
l@273: bool setup(BeagleRTContext *context, void *userData)
l@273: {
l@273:     // tell the scope how many channels and the sample rate
l@273:     scope.setup(3, context->audioSampleRate);
l@273: 
l@273:     gPhase = 0;
l@273:     gInverseSampleRate = 1.0f/context->audioSampleRate;
l@273:     
l@273: 	return true;
l@273: }
l@273: 
l@273: float lastOut = 0.0;
l@273: float lastOut2 = 0.0;
l@273: void render(BeagleRTContext *context, void *userData)
l@273: {
l@273:     // iterate over the audio frames and create three oscillators, seperated in phase by PI/2
l@273:     for (unsigned int n=0; n<context->audioFrames; n++){
l@273:         float out = 0.8f * sinf(gPhase);
l@273:         float out2 = 0.8f * sinf(gPhase - M_PI/2);
l@273: 		float out3 = 0.8f * sinf(gPhase + M_PI/2);
l@273: 		gPhase += 2.0 * M_PI * gFrequency * gInverseSampleRate;
l@273: 		if(gPhase > 2.0 * M_PI)
l@273: 			gPhase -= 2.0 * M_PI;
l@273: 			
l@273: 		// log the three oscillators to the scope
l@273:         scope.log(out, out2, out3);
l@273:         
l@273:         // optional - tell the scope to trigger when oscillator 1 becomes less than oscillator 2
l@273:         // note this has no effect unless trigger mode is set to custom in the scope UI
l@273:         if (lastOut >= lastOut2 && out < out2){
l@273:             scope.trigger();
l@273:         }
l@273:         
l@273:         lastOut = out;
l@273:         lastOut2 = out2;
l@273:     }
l@273: }
l@273: 
l@273: void cleanup(BeagleRTContext *context, void *userData)
l@273: {
l@273: 
l@273: }