Use restricted interrupt priority levels

RE: Use restricted interrupt priority levels

Øyvind Karlsen — Mon, 27 Jun 2016 06:20:43 GMT

I don't really have a better explanation than that this is how it is implemented, there's more info on the infocenter for nRF51 and nRF52. The nRF52 is using an M4F processor and has access to more priorities.

RE: Use restricted interrupt priority levels

Nikolaus Wittenstein — Fri, 24 Jun 2016 13:13:11 GMT

I understand the restricted access to priority 0, but not to priority 2—if I can use priority 1, then I'm interrupting anything at priority 2 anyway, meaning I should be able to use priority 2 as well if I want. Or is there some reason that's not the case?

Thanks!

-Nikolaus

RE: Use restricted interrupt priority levels

Øyvind Karlsen — Fri, 24 Jun 2016 09:01:49 GMT

Hi,

The SoftDevice needs to be able to interrupt the radio notification in order to start radio activity, this is why it has restricted access to priority 0. Likewise the SoftDevice needs priority 2 so that it is able to deal with its less time critical tasks. If you want to be able to run freely of the SoftDevice for a period, schedule a timeslot.

In general the interrupt that is triggered first is the one that is handled first, a higher priority interrupt will interrupt a lower priority interrupt. If you have two equal priority interrupts firing at the same time, the one with the lowest ISR number will be handled first.

Best regards,

Øyvind