Increase the number of Interrupt pins

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1

Hi,

According to the documentation, only a subset of pins on each board can have an interrupt attached.

Is there a trick (or method) for increasing the number of interrupt pins on an Arduino board?
Is there a library that people use to achieve this?

Any guidance would be much appreciated.

Regards
Cillian

2

Any I/O pin on an UNO can function as an interrupt - with a caveat. Pins other than 2 & 3 can only function as 'pin change' interrupts. That is, there's no rising/falling option, either transition will trigger the interrupt.

There *are * libraries to simplify using pin change interrupts - IDE -> sketch/include library/manage libraries/ filter . See also the processor datasheet.

3

Thank you.

4

Are you sure you need more interrupts? A lot of interaction with Arduino looks on the face of it like interrupts are the way to go, but they are often unnecessary and decent design of the sketch ensures that external influences are checked often enough just by normal reads of the pins.