P1 Pin Mapping & Interrupts

[mblackler]

Hey Everyone,

We’re looking at adding a Watchdog, and I require an interrupt-able pin on my P1 to receive a nudge from the Watchdog, which I can then respond back to on a separate GPIO pin to say “don’t worry, I’m here”.

I’ve been trying to find a good P1 pin to attach this Watchdog to, but I cannot find a table that maps the pins, the identifies whether a pin is a) interruptible and b) whether the pin can be used in conjunction with other pins when it is tied to an interrupt.

I’ve dug around and can’t find the doc that would have this detail in.

Any pointers?

Thanks,

Matthew

[mikemoy]

Have you taken a look at this page?
https://docs.particle.io/reference/firmware/photon/#interrupts

[ScruffR]

This discussion will also apply to the P1

Does the Electron support external interrupts?

Yup, the docs lag behind a few years here The list of availabe interrupt pins for the Electron is similar to the Photon’s. To know which pins share EXTI lines with other pins you’d need to look at the GPIO numbers in the pin overview in the datasheets where Px## stands for Port x bit ## and all bits with the same number share the same EXTI line across all ports. So out of Ports A, B, C & D only one ## can have an independent interrupt assigned. e.g. for the Photon you read D0 and A…

[mblackler]

Thanks ScruffR, that nailed it. Thanks!