Demonstrate the use of an external interrupt to toggle an LED On/Off using LPC2148 Microcontroller

The external interrupts are the interrupts received from the (external) devices interfaced with the microcontroller. By using P0.3 port line we are generating external interrupt (EINT1).Short JP12, when we press the switch SW12 the port line goes low & the external interrupt occurs at port line P0.16. The microcontroller gets interrupts in whatever it is doing and jumps to the vector table to perform the interrupt service routine.