comparison projects/7segment/render.cpp @ 268:8d80eda512cd prerelease

Added new overlay for using PRU0 or PRU1, a script to halt board on button press, and several example projects

+/*
+ * render.cpp
+ *
+ *  Created on: Oct 24, 2014
+ *      Author: parallels
+ */
+
+
+#include <BeagleRT.h>
+#include <Utilities.h>
+
+#define NUM_PINS 12
+
+// Breadboard wiring layout:
+// 11 10 12 9  8  7
+// [ LED DISP ]
+// 1  2  3  6  4  5
+
+// Organised by display segments:
+// e d . X c g b X X X f a
+const int kPins[NUM_PINS] = {P8_07, P8_08, P8_09, P8_10, P8_11, P8_12,
+							 P8_15, P8_16, P8_27, P8_28, P8_29, P8_30};
+
+// Indices into the above array: pins 12, 9, 8, 6
+const int kDigits[4] = {9, 8, 7, 3};
+
+int gCurrentlyDisplayingDigit = 0;
+int gDigitDisplayTime = 0;
+const int kDigitMaxDisplayTime = 44;
+
+int gState = 0;
+int gStateCounter = 0;
+const int kMaxState = 25;
+
+// . g f e d c b a
+//const unsigned char kBELA[4] = {0x7C, 0x79, 0x38, 0x77};
+const unsigned char kBELA[4] = {0x7C, 0x7B, 0x38, 0x5F};
+const unsigned char kPerimeter[6] = {0x01, 0x02, 0x04, 0x08, 0x10, 0x20};
+
+int gCharacterToDisplay[4] = {0, 0, 0, 0};
+	
+// setup() 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.
+
+bool setup(BeagleRTContext *context, void *userData)
+{	
+	// This project makes the assumption that the audio and digital
+	// sample rates are the same. But check it to be sure!
+	if(context->audioFrames != context->digitalFrames) {
+		rt_printf("Error: this project needs the audio and digital sample rates to be the same.\n");
+		return false;
+	}
+	
+	for(int i = 0; i < NUM_PINS; i++) {
+		pinModeFrame(context, 0, kPins[i], OUTPUT);
+	}
+
+	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(BeagleRTContext *context, void *userData)
+{
+	for(unsigned int n = 0; n < context->audioFrames; n++) {
+		// Check for rotation between digits
+		if(--gDigitDisplayTime <= 0) {
+			gCurrentlyDisplayingDigit = (gCurrentlyDisplayingDigit + 1) % 4;
+			gDigitDisplayTime = kDigitMaxDisplayTime;
+		}
+	
+		// Write the currently displaying digit low and the rest high
+		for(int i = 0; i < 4; i++)
+				digitalWriteFrameOnce(context, n, kPins[kDigits[i]], HIGH);
+		digitalWriteFrameOnce(context, n, kPins[kDigits[gCurrentlyDisplayingDigit]], LOW);
+		
+		// Write the digit to the other outputs
+		digitalWriteFrameOnce(context, n, kPins[11],
+			gCharacterToDisplay[gCurrentlyDisplayingDigit] & 0x01);	// a
+		digitalWriteFrameOnce(context, n, kPins[6], 
+			gCharacterToDisplay[gCurrentlyDisplayingDigit] & 0x02);	// b
+		digitalWriteFrameOnce(context, n, kPins[4], 
+			gCharacterToDisplay[gCurrentlyDisplayingDigit] & 0x04);	// c
+		digitalWriteFrameOnce(context, n, kPins[1],
+			gCharacterToDisplay[gCurrentlyDisplayingDigit] & 0x08);	// d
+		digitalWriteFrameOnce(context, n, kPins[0],
+			gCharacterToDisplay[gCurrentlyDisplayingDigit] & 0x10);	// e
+		digitalWriteFrameOnce(context, n, kPins[10],
+			gCharacterToDisplay[gCurrentlyDisplayingDigit] & 0x20);	// f
+		digitalWriteFrameOnce(context, n, kPins[5],
+			gCharacterToDisplay[gCurrentlyDisplayingDigit] & 0x40);	// g
+		digitalWriteFrameOnce(context, n, kPins[2],
+			gCharacterToDisplay[gCurrentlyDisplayingDigit] & 0x80);	// .
+			
+		// Check for changing state
+		if(--gStateCounter <= 0) {
+			gState = (gState + 1) % kMaxState;
+			if(gState != (kMaxState - 1)) {
+				for(int i = 0; i < 4; i++)
+					gCharacterToDisplay[i] = 1 << (gState % 6);
+				gStateCounter = 2000;
+			}
+			else {
+				for(int i = 0; i < 4; i++)
+					gCharacterToDisplay[i] = kBELA[i];
+				gStateCounter = 50000;
+			}
+		}
+	}
+}
+
+// cleanup() is called once at the end, after the audio has stopped.
+// Release any resources that were allocated in setup().
+
+void cleanup(BeagleRTContext *context, void *userData)
+{
+	
+}