ADC ( analog-to-digital converter) Interrupt.

PORTB Change interrupts (any one of the upper four Port B pins.

Pins RB0, RB1, RB2 for external hardware interrupts (INT0, INT1, INT2).

INTERRUPTS IN PIC18F452įollowing interrupts sources are present in PIC18F452

Hardware Interrupt:These interrupts are sent by external hardware devices at certain pins of microcontroller. Software Interrupt: It comes from a program that is executed by microcontroller or we can say that it is generated by internal peripherals of the microcontroller and requests the processor to hold the running of program and go to make an interrupt. There are 2 types of interrupts for PIC microcontroller that can cause break. For example, to divide the work between them they will send signals between them.

In the multi-processor system, the microcontrollers can send interrupts to each other to communicate.

For example, division by 0 will causes an interrupt.

During execution of the program, the microcontroller can also send interrupts to itself to report an error in the code.

Through external hardware devices like pressing specific key on the keyboard, which sends Interrupt to the microcontroller to read the information of the pressed key.

The request to the microcontroller to stop to perform the current program temporarily can come from various sources: It means when external device finishes the task imposed on it, the microcontroller will be notified that it can access and receive the information and use it.Interrupts are just like waiting for the phone to ring. Interrupt is the signal which is sent to the microcontroller to mark the event that requires immediate attention.This signal requests the microcontroller to stop to perform the current program temporarily time to execute a special code. It needs to wait and check whether the new information has arrived not. Polling method is just like picking up our phone after every few seconds to see if we have a call.The main drawback of this method is the waste of time of microcontroller. The microcontroller accesses that device at the exact time interval and gets the required information. We fix the time interval in which microcontroller has to contact the external device. In this method, the external devices are not independent. There are two methods of communication between the microcontroller and the external device:

EXAMPLE OF USING INTERRUPTS IN PIC18F452.

Mikroc uart interrupt example