ledswitch.c

LPC 2129 base source code for LED blinking

//////////////////////////////////////////////////////////////////////////////
//
// Philips LPC2129 ARM7TDMI LED/Switch Example
//
// This example demonstrates writing to and reading from 
// the GPIO port.
// (1) flash the LED 10 times
// (2) wait for key-press, turn off LED if key is pressed
//
// WinARM example by Martin THOMAS, Kaiserslautern, Germany
// ([e-mail])
// http://www.siwawi.arubi.uni-kl.de/avr_projects
//////////////////////////////////////////////////////////////////////////////

#include "lpc21xx_keil.h"

// olimex LPC-P2129: buttons on P0.10/P0.11 (active low)
#define BUT1PIN 	10
#define BUT2PIN 	11
// olimex LPC-P2129: LEDs on P0.12/P0.13 (active low)
#define LED1PIN  	12
#define LED2PIN  	13

static void delay(void )
{
	volatile int i,j;

	for (i=0;i<100;i++)
		for (j=0;j<1000;j++);
}
  
int main(void)
{
	int i;
		
	MAMCR = 2;	// MAM functions fully enabled

	IODIR0 |= (1<<LED1PIN)|(1<<LED2PIN); // define LED-Pins as outputs
	IOSET0 = (1<<LED1PIN)|(1<<LED2PIN); // set Bits = LEDs off (active low)
	IODIR0 &= ~((1<<BUT1PIN)|(1<<BUT2PIN));// define Button-Pins as inputs
		
	i=0;
	while (i<10)	
	{
		IOCLR0 = (1<<LED1PIN);	
		IOSET0 = (1<<LED2PIN);	
		delay();
		IOSET0 = (1<<LED1PIN);
		IOCLR0 = (1<<LED2PIN);	
		delay();
		i++;
	}
	
	while (1)	
	{
		if (IOPIN0 & (1<<BUT1PIN))	{ // true if button released (active low)
			IOCLR0 = (1<<LED1PIN);		// clear I/O bit -> LED on (active low)
		}
		else {
			IOSET0 = (1<<LED1PIN);		// set I/O bit -> LED off (active low)
		}
		
		if (IOPIN0 & (1<<BUT2PIN))	{ // true if button released (active low)
			IOCLR0 = (1<<LED2PIN);		// clear I/O bit -> LED on (active low)
		}
		else {
			IOSET0 = (1<<LED2PIN);		// set I/O bit -> LED off (active low)
		}
	}
	
	return 0; // never reached
}