robert@464: /*
robert@464:  ____  _____ _        _    
robert@464: | __ )| ____| |      / \   
robert@464: |  _ \|  _| | |     / _ \  
robert@464: | |_) | |___| |___ / ___ \ 
robert@464: |____/|_____|_____/_/   \_\
robert@464: 
robert@464: The platform for ultra-low latency audio and sensor processing
robert@464: 
robert@464: http://bela.io
robert@464: 
robert@464: A project of the Augmented Instruments Laboratory within the
robert@464: Centre for Digital Music at Queen Mary University of London.
robert@464: http://www.eecs.qmul.ac.uk/~andrewm
robert@464: 
robert@464: (c) 2016 Augmented Instruments Laboratory: Andrew McPherson,
robert@464:   Astrid Bin, Liam Donovan, Christian Heinrichs, Robert Jack,
robert@464:   Giulio Moro, Laurel Pardue, Victor Zappi. All rights reserved.
robert@464: 
robert@464: The Bela software is distributed under the GNU Lesser General Public License
robert@464: (LGPL 3.0), available here: https://www.gnu.org/licenses/lgpl-3.0.txt
robert@464: */
robert@464: 
robert@464: 
robert@464: #include <Bela.h>
robert@464: 
robert@464: const int kStepLengthSlow = 1000;
robert@464: const int kStepLengthFast = 500;
robert@464: 
robert@464: int gStepLengthSamples = kStepLengthSlow;
robert@464: 
robert@464: const int gPinA1 = P8_27;
robert@464: const int gPinA2 = P8_28;
robert@464: const int gPinB1 = P8_29;
robert@464: const int gPinB2 = P8_30;
robert@464: const int gPinServo = P9_16;
robert@464: 
robert@464: int gStepCounter = 0;
robert@464: int gPhase = 0;
robert@464: 
robert@464: int gServoCounter = 0;
robert@464: 
robert@464: 
robert@464: enum {
robert@464: 	kStateMoveRight1 = 0,
robert@464: 	kStateMoveLeft1,
robert@464: 	kStateMoveRight2,
robert@464: 	kStateMoveLeft2,
robert@464: 	kStateMoveRight3,
robert@464: 	kStateMoveLeft3,
robert@464: 	kStateSpin,
robert@464: 	kStateMax
robert@464: };
robert@464: 
robert@464: int gState = 0;
robert@464: int gStateCounter = 0;
robert@464: 
robert@464: // setup() is called once before the audio rendering starts.
robert@464: // Use it to perform any initialisation and allocation which is dependent
robert@464: // on the period size or sample rate.
robert@464: //
robert@464: // userData holds an opaque pointer to a data structure that was passed
robert@464: // in from the call to initAudio().
robert@464: //
robert@464: // Return true on success; returning false halts the program.
robert@464: 
robert@464: bool setup(BelaContext *context, void *userData)
robert@464: {	
robert@464: 	// This project makes the assumption that the audio and digital
robert@464: 	// sample rates are the same. But check it to be sure!
robert@464: 	if(context->audioFrames != context->digitalFrames) {
robert@464: 		rt_printf("Error: this project needs the audio and digital sample rates to be the same.\n");
robert@464: 		return false;
robert@464: 	}
robert@464: 	
robert@464: 	pinMode(context, 0, gPinA1, OUTPUT);
robert@464: 	pinMode(context, 0, gPinA2, OUTPUT);
robert@464: 	pinMode(context, 0, gPinB1, OUTPUT);
robert@464: 	pinMode(context, 0, gPinB2, OUTPUT);
robert@464: 	pinMode(context, 0, gPinServo, OUTPUT);
robert@464: 		
robert@464: 	return true;
robert@464: }
robert@464: 
robert@464: // render() is called regularly at the highest priority by the audio engine.
robert@464: // Input and output are given from the audio hardware and the other
robert@464: // ADCs and DACs (if available). If only audio is available, numMatrixFrames
robert@464: // will be 0.
robert@464: 
robert@464: void render(BelaContext *context, void *userData)
robert@464: {
robert@464: 	for(unsigned int n = 0; n < context->audioFrames; n++) {
robert@464: 		if(gPhase == 0 || gPhase == 1) {
robert@464: 			digitalWriteOnce(context, n, gPinB1, HIGH);
robert@464: 			digitalWriteOnce(context, n, gPinB2, LOW);
robert@464: 		}
robert@464: 		else {
robert@464: 			digitalWriteOnce(context, n, gPinB1, LOW);
robert@464: 			digitalWriteOnce(context, n, gPinB2, HIGH);			
robert@464: 		}
robert@464: 		
robert@464: 		if(gPhase == 1 || gPhase == 2) {
robert@464: 			digitalWriteOnce(context, n, gPinA1, HIGH);
robert@464: 			digitalWriteOnce(context, n, gPinA2, LOW);
robert@464: 		}
robert@464: 		else {
robert@464: 			digitalWriteOnce(context, n, gPinA1, LOW);
robert@464: 			digitalWriteOnce(context, n, gPinA2, HIGH);			
robert@464: 		}
robert@464: 		
robert@464: 		if(--gServoCounter > 0) 
robert@464: 			digitalWriteOnce(context, n, gPinServo, HIGH);
robert@464: 		else
robert@464: 			digitalWriteOnce(context, n, gPinServo, LOW);
robert@464: 		
robert@464: 		if(++gStepCounter >= gStepLengthSamples) {
robert@464: 			gStateCounter++;
robert@464: 			
robert@464: 			switch(gState) {
robert@464: 				case kStateMoveRight1:
robert@464: 				case kStateMoveRight2:
robert@464: 				case kStateMoveRight3:
robert@464: 					gPhase = (gPhase + 1) & 3;
robert@464: 					break;
robert@464: 				case kStateMoveLeft1:
robert@464: 				case kStateMoveLeft2:
robert@464: 				case kStateMoveLeft3:				
robert@464: 					gPhase = (gPhase + 3) & 3;	
robert@464: 					break;
robert@464: 				case kStateSpin:
robert@464: 					gPhase = (gPhase + 1) & 3;
robert@464: 					break;		
robert@464: 			}
robert@464: 			
robert@464: 			if(gState == kStateSpin) {
robert@464: 				if(gStateCounter >= 48) {
robert@464: 					gStateCounter = 0;
robert@464: 					gState = 0;
robert@464: 					gStepLengthSamples = kStepLengthSlow;
robert@464: 				}				
robert@464: 			}
robert@464: 			else {
robert@464: 				if(gStateCounter >= 16) {
robert@464: 					gStateCounter = 0;
robert@464: 					gState++;
robert@464: 					if(gState & 1)
robert@464: 						gServoCounter = 120;
robert@464: 					else
robert@464: 						gServoCounter = 80;
robert@464: 					if(gState == kStateSpin)
robert@464: 						gStepLengthSamples = kStepLengthFast;
robert@464: 				}
robert@464: 			}
robert@464: 			
robert@464: 			gStepCounter = 0;
robert@464: 		}
robert@464: 	}
robert@464: }
robert@464: 
robert@464: // cleanup() is called once at the end, after the audio has stopped.
robert@464: // Release any resources that were allocated in setup().
robert@464: 
robert@464: void cleanup(BelaContext *context, void *userData)
robert@464: {
robert@464: 	
robert@464: }