opdracht 2.1

Microcontrollers/opdracht 2.1/main.c

@@ -0,0 +1,86 @@
+/* ---------------------------------------------------------------------------
+** This software is in the public domain, furnished "as is", without technical
+** support, and with no warranty, express or implied, as to its usefulness for
+** any purpose.
+**
+** ioisr.c
+**
+** Beschrijving:	ISR on PORTD demonstrattion  
+** Target:			AVR mcu
+** Build:			avr-gcc -std=c99 -Wall -O3 -mmcu=atmega128 -D F_CPU=8000000UL -c ioisr.c
+**					avr-gcc -g -mmcu=atmega128 -o ioisr.elf ioisr.o
+**					avr-objcopy -O ihex ioisr.elf ioisr.hex 
+**					or type 'make'
+** Author: 			dkroeske@gmail.com
+** -------------------------------------------------------------------------*/
+
+#define F_CPU 8e6
+#include <avr/io.h>
+#include <util/delay.h>
+#include <avr/interrupt.h>
+
+
+/******************************************************************
+/* 
+short:			Busy wait number of millisecs
+inputs:			int ms (Number of millisecs to busy wait)
+outputs:	
+notes:			Busy wait, not very accurate. Make sure (external)
+				clock value is set. This is used by _delay_ms inside
+				util/delay.h
+Version :    	DMK, Initial code
+*******************************************************************/
+void wait( int ms ) {
+	for (int i=0; i<ms; i++) {
+		_delay_ms( 1 );		// library function (max 30 ms at 8MHz)
+	}
+}
+
+/*****************************************************************
+short:			ISR INT0
+inputs:
+outputs:
+notes:			Set PORTD.5
+Version :    	DMK, Initial code
+*******************************************************************/
+ISR( INT0_vect ) {
+    PORTD |= (1<<5);		
+}
+
+/******************************************************************
+short:			ISR INT1
+inputs:
+outputs:
+notes:			Clear PORTD.5
+Version :    	DMK, Initial code
+*******************************************************************/
+ISR( INT1_vect ) {
+    PORTD &= ~(1<<5);		
+}
+
+/******************************************************************
+short:			main() loop, entry point of executable
+inputs:
+outputs:
+notes:			Slow background task after init ISR
+Version :    	DMK, Initial code
+*******************************************************************/
+int main( void ) {
+	// Init I/O
+	DDRD = 0xF0;			// PORTD(7:4) output, PORTD(3:0) input	
+
+	// Init Interrupt hardware
+	EICRA |= 0x0B;			// INT1 falling edge, INT0 rising edge
+	EIMSK |= 0x03;			// Enable INT1 & INT0
+	
+	// Enable global interrupt system
+	//SREG = 0x80;			// Of direct via SREG of via wrapper
+	sei();				
+
+	while (1) {
+		PORTD ^= (1<<7);	// Toggle PORTD.7
+		wait( 500 );								
+	}
+
+	return 1;
+}