PORTB Interrupt Example

PORTB interrupts are used for instantaneous response for changes to Pins 4, 5, 6, 7 on PORTB. Further more, the interrupt will even wake the PIC from a Sleep instruction, so your device can be in low power mode (the PIC can draw as low as 0.1u Amps while in Sleep mode), and be instantly awoken when there is a change on PORTB.


One precaution to be aware of is not to forget to read the contents of PORTB within the ISR (Interrupt Service Routine). This is a hardware requirement to clear the mismatch condition that triggers the PORTB interrupt flag. The following program shows how to create a PORTB interrupt routine, that puts the PIC to Sleep after enabling the interrupt, and upon any pin change on PORTB 7:4, the PIC will wake up (thanks to the PORTB interrupt) and the change will be mirrored to PORTC.

See this tutorial for more information http://digital-diy.com/micro/site/swordfish/83-swordfish-code-snippet-interru...

Category:

Education

Tags:

• PORTB
• interrupts
• pic
• micro
• microcontroller

[hornyakd92]

which software is this? isis professional?

[Mubasher77]

difficult to understand