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:

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.

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