Week 12: Segment 1: USe of Pin Change Interrupts on the Arduino

This segment focuses on 'pin change interrupts' for the detection of events that occur sparsely and randomly such as a touch pad or button event. The difference between 'external' and 'pin change' interrupts is that the external interrupts only react to pins 2 and 3 on the Arduino, while the pin change interrupts can be used on all pins. The drawback of pin change interrupts is that the triggering pin usually needs to be detected in a second step, and that only pin change events can be defined as interrupts, and not specific transitions such as rising and falling edge.

Goals:

• Understand the use of pin change interrupts that are triggered by pin events.
• Learn to read out an array of switches.

In-Class Project:

• Set up five switches and respond to them via pin change interrupts.

Materials for this segment:

• Watch the video on the right 
  
• Arduino sketch featured in the video (see link below video).
• The ATmega328p data sheet. Look at Chapters 11 (interrupts, a table of the interrupt vectors is given here) 12 (external and pin change interrupts) and 13 (input/output ports) 

Main Arduino sketch used in the tutorial:

t16_pinchangeinterrupts_switches.zip
File Size:	2 kb
File Type:	zip

Download File

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