External Interrupt for AT89C51
Category: AT89C51
Designer: RANA MUHAMMAD ADNAN KHALIL
Notes
This circuit is designed and simulated in Proteus 7.10 and firmware is written in KEIL. The microcontroller AT89C51 is used for demo of external interrupt. 1. In this circuit you will learn how external interrupt of AT89C51 is used. 2. When interrupt occur, the program counter of microcontroller goes to interrupt address and executes interrupt service routine. 3. In this circuit LED is toggled in interrupt service routine. 4. AT89C51 supports two external interrupts, INT0 and INT1. 5. INT0 is used in this circuit. 6. LED is placed at pin P2.0 of PORT 2. 7. Download the program and modify the interrupt service routine according to your need. More circuits with concepts will be added soon.