giuliomoro@23:     /*
giuliomoro@19:  *
giuliomoro@19:  * First assignment for ECS732 RTDSP, to implement a 2-way audio crossover
giuliomoro@19:  * using the BeagleBone Black.
giuliomoro@19:  *
giuliomoro@19:  * Andrew McPherson and Victor Zappi
giuliomoro@19:  * Queen Mary, University of London
giuliomoro@19:  */
giuliomoro@19: 
andrewm@22: #include "../../include/render.h"
giuliomoro@19: #include <cmath>
giuliomoro@19: #include <rtdk.h>
giuliomoro@19: 
giuliomoro@19: /* TASK: declare any global variables you need here */
giuliomoro@19: 
giuliomoro@19: // initialise_render() is called once before the audio rendering starts.
giuliomoro@19: // Use it to perform any initialisation and allocation which is dependent
giuliomoro@19: // on the period size or sample rate.
giuliomoro@19: //
giuliomoro@19: // userData holds an opaque pointer to a data structure that was passed
giuliomoro@19: // in from the call to initAudio().
giuliomoro@19: //
giuliomoro@19: // Return true on success; returning false halts the program.
giuliomoro@20: int gNumDigitalFrames=0;
giuliomoro@20: bool initialise_render(int numAnalogChannels, int numDigitalChannels, int numAudioChannels,
giuliomoro@20: 					   int numAnalogFramesPerPeriod,
giuliomoro@19: 					   int numAudioFramesPerPeriod,
giuliomoro@20: 					   float analogSampleRate, float audioSampleRate,
giuliomoro@33: 					   void *userData, RTAudioSettings* settings)
giuliomoro@19: {
giuliomoro@20: 	gNumAnalogChannels=numAnalogChannels;
giuliomoro@23:     gNumDigitalChannels=numDigitalChannels;
giuliomoro@19: 	return true;
giuliomoro@19: }
giuliomoro@19: 
giuliomoro@19: // render() is called regularly at the highest priority by the audio engine.
giuliomoro@19: // Input and output are given from the audio hardware and the other
giuliomoro@20: // ADCs and DACs (if available). If only audio is available, numAnalogFrames
giuliomoro@19: // will be 0.
giuliomoro@19: 
giuliomoro@19: long int gCountFrames=0;
giuliomoro@20: void render(int numAnalogFrames, int numDigitalFrames, int numAudioFrames, float *audioIn, float *audioOut,
giuliomoro@20: 			float *analogIn, float *analogOut, uint32_t *digital)
giuliomoro@19: /*
giuliomoro@23: we assume that gNumAnalogChannels=8, numAnalogFrames==8 and  numDigitalFrames==numAudioFrames
giuliomoro@19:  * */
giuliomoro@19: {
giuliomoro@23: 	if((gCountFrames&31)==0){ //every 32 frames...
giuliomoro@23:         //ANALOG channels
giuliomoro@23: 		analogWrite(0, 0, analogRead(0,0)); // read the input0 at frame0  and write it to output0 frame0. Using analogWrite will fill the rest of the buffer with the same value
giuliomoro@23:                                             // The value at the last frame will persist through the successive buffers until is set again.
giuliomoro@23:                                             // This effectively is a pass-through with downsampling by 32 times
giuliomoro@23:         analogWrite(3, 0, 1.0);  // write 1.0 to channel3 from frame0 to the end of the buffer
giuliomoro@23:         analogWrite(3, 4, 0.1);  // write 0.1  to channel3 from frame4 to the end of the buffer
giuliomoro@23:         analogWriteFrame(3,6,0.2); //write 0.2 to channel3 only on frame 6
giuliomoro@23:         //this buffer for channel 3 will look like this:  1 1 1 1 0.1 0.1 0.2 0.1 
giuliomoro@23:         //the next buffers for channel 3 will be filled up with 0.1 ....
giuliomoro@23:         //DIGITAL channels
giuliomoro@23:         digitalWrite(P8_07,0,GPIO_HIGH); //sets all the frames  to HIGH for channel 0
giuliomoro@23:         digitalWriteFrame(P8_07,4,GPIO_LOW); //only frame 4 will be LOW  for channel 0
giuliomoro@23:         // in this buffer the frames of channel 0 will look like this: 1 1 1 1 0 1 1 1 ...... 1 
giuliomoro@23:         // in the next buffer each frame of channel 0 will be initialized to 1 (the last value of this buffer)
giuliomoro@23:         digitalWrite(P8_08,0,GPIO_HIGH);
giuliomoro@23:         digitalWrite(P8_08,2,GPIO_LOW);
giuliomoro@23:         digitalWrite(P8_08,4,GPIO_HIGH);
giuliomoro@23:         digitalWrite(P8_08,5,GPIO_LOW);
giuliomoro@33:         setDigitalDirection(P9_16,0,GPIO_INPUT); // set channel 10 to input
giuliomoro@23:         // in this buffer the frames of channel 1 will look like this: 1 1 0 0 1 0 0 0 .... 0
giuliomoro@23:         // in the next buffer each frame of channel 1 will be initialized to 0 (the last value of this buffer)
giuliomoro@19: 	}
giuliomoro@23: 	for(int n=0; n<numAudioFrames; n++){
giuliomoro@23: 		for(int c=0; c<gNumAudioChannels; c++){
giuliomoro@23: 			audioOut[n*gNumAudioChannels + c]=audioIn[n*gNumAudioChannels + c];
giuliomoro@23: 		}
giuliomoro@33:         //use digital channels 2-8 to create a 7 bit binary counter
giuliomoro@33:         digital[n]=digital[n] & (~0b111111100); // set to zero (GPIO_OUTPUT) the bits in the lower word
giuliomoro@33:         digital[n]=digital[n] & ((~0b111111100<<16) | 0xffff ); //initialize to zero the bits in the higher word (output value)
giuliomoro@33:         digital[n]=digital[n] | ( ((gCountFrames&0b1111111)<<(16+2)) ) ;  // set the bits in the higher word to the desired output value, keeping the lower word unchanged
giuliomoro@33:         digitalWriteFrame(P8_29,n,digitalRead(P8_30,n)); // echo the input from from channel 15 to channel 14
giuliomoro@33:         digitalWriteFrame(P8_28,n,digitalRead(P9_16,n)); // echo the input from from channel 10 to channel 13
giuliomoro@33:         setDigitalDirection(P8_30,0,GPIO_INPUT); //set channel 15 to input
giuliomoro@33: 		gCountFrames++;
giuliomoro@19: 	}
giuliomoro@23: 
giuliomoro@23: 	for(int n=0; n<numAnalogFrames; n++){
giuliomoro@23:     	analogWriteFrame(1,n,(gCountFrames&8191)/8192.0); // writes a single frame. channel 1 is a ramp that follows gCountFrames
giuliomoro@23:     	analogWriteFrame(2,n,analogRead(2,n)); // writes a single frame. channel2 is just a passthrough
giuliomoro@23: //		rt_printf("Analog out frame %d :",n);
giuliomoro@23: //		for(int c=0; c<gNumAnalogChannels; c++)
giuliomoro@23: //			rt_printf("%.1f ",analogOut[n*gNumAnalogChannels + c]);
giuliomoro@23: //		rt_printf("\n");
giuliomoro@19: 	}
giuliomoro@23: 	return;
giuliomoro@23: 
giuliomoro@19: }
giuliomoro@19: // cleanup_render() is called once at the end, after the audio has stopped.
giuliomoro@19: // Release any resources that were allocated in initialise_render().
giuliomoro@19: 
giuliomoro@19: void cleanup_render()
giuliomoro@19: {
giuliomoro@19: 	/* TASK:
giuliomoro@19: 	 * If you allocate any memory, be sure to release it here.
giuliomoro@19: 	 * You may or may not need anything in this function, depending
giuliomoro@19: 	 * on your implementation.
giuliomoro@19: 	 */
giuliomoro@19: }