Whoever needs his products or services goes to him and buy it. While the method of Interrupt is similar to a shopkeeper. This is similar to a microcontroller continuously monitoring the status of all devices attached to it. The method of polling is similar to a salesperson, who goes door-to-door to requesting to buy his product or service. Here is an analogy to understand the difference better. The microcontroller wants to respond only when an interrupt occurs. Consider if this problem is addressed using Interrupts. This processes of continuous monitoring is known as POLLING. This is not an efficient way of programming as it consumes all its processing time for monitoring. Read the status of push button switches and change controls accordingly.Consider this application without using interrupt, the programmer wants to continuously do the following tasks. It contains push button switches to select song, control volume etc. The microcontroller should be programmed to convert the data stored in MP3 files to electrical signal and to change controls according to the status of push button switches. Need for InterruptsĬonsider a MP3 player which build around microcontroller.

When the mobile conversation is ended you will go back to the main service routine of taking coffee. This initiates your mobile phone conversation which is similar to executing ISR. You can think the main service routine as taking coffee and the ringing of mobile phone is causes interrupt in taking coffee. This process is similar to ISR execution. When you have finished the conversation, you will go back to take coffee. You stop taking coffee and answer the call. So what is an Interrupt…?Īs the name suggests Interrupts are special events that requires immediate attention, it stops a microcontroller/ microprocessor from the running task and to serve a special task known as Interrupt Service Routine (ISR) or Interrupt Handler. Almost all the real time applications are implemented using Interrupts. Interrupt is the one of the most powerful feature in embedded applications. 4.1.8 RBIF – RB Port Change Interrupt Flag.4.1.7 INTF – RB0/INT External Interrupt Flag.4.1.6 TMR0IF – Timer 0 Overflow Interrupt Flag.4.1.5 RBIE – RB Port Change Interrupt Enable.4.1.4 INTE – RB0/INT External Interrupt Enable.4.1.3 TMR0IE – Timer 0 Overflow Interrupt Enable.4.1.2 PEIE – Peripheral Interrupt Enable.

Diptrace external pins