Program to Blink LED interfaced with LPC2148 microcontroller

LPC2148 is a 32-bit microcontroller by NXP. I discuss a simple LED interface program interfaced with LPC2148 microcontroller to make you understand its register and PINSEL functions.

Program:

	#include <LPC214X.H> // Select Header file
	long i;
	int main()
	{
	IODIR1=0xffffffff; //This register individually controls the direction of each port pin.
	IOCLR1=0xffffffff; //This register controls the state of output pins.
	While(1) //Infinite loop
	{
	IOSET1=0x00FF0000; //This register controls the state of output pins in conjunction with the IOCLR register.
	For(i=0;i<100000;i++); //Delay
	for(i=0;i<100000;i++);
	IOCLR1=0xffffffff;
	for(i=0;i<100000;i++);
	for(i=0;i<100000;i++);
	}
	}

view raw LPC2148 hosted with ❤ by GitHub

Theory:

In the above code, there are 3 main instructions are used- ISOET0/1, IODIR0/1 and IOCLR0/1. Every instruction has its own meaning as explained in Table 4. The above is taken on Fast GPIO port P1 on pins 16-23. Each decimal number in 0x00000000 defines the 4-bit, so the total comes out to be 32-bit. In GPIO port P1, 0-15 pins are reserved so you cannot direct output on these pins. Whereas 24, 26, and 27 pins of GPIO port P0 are reserved.