CHANGE interrupt on any pin?

Projects Programming
1

Can any of the UNO's pins be used as a CHANGE interrupt? I thought I have heard so, but the Arduino reference doesn't make note of this.

2

There are two interrupt pins on the UNO.
Pin D2 and pin D3.
These are interrupts 0 and 1.
You can assign rising, falling, change, and low.

3

Mr. Gammon has a great discussion here:

4

Any of the Uno's twenty or so I/O pins can be used as a change interrupt.

Read the gammon web page.

5

There seems to be conflicting information. How would I attach an CHANGE interrupt to pin 8, for example (if possible).

6

See the Arduino Pin Change Interrupt page

7

Not sure what "reference" you looked at. From the Arduino Uno page:

External Interrupts: 2 and 3. These pins can be configured to trigger an interrupt on a low value, a rising or falling edge, or a change in value. See the attachInterrupt() function for details.

Regards,
Ray L.

8

Only the DUE can use interrupt on almost any pin.

10

See my link. You can use a change interrupt on almost every pin of an Uno. There are only just 3 different interrupt routines for them. So in the routine it's up to you to check which pin caused the trigger/changed.

And for a lot of things this is fast and efficient enough.