Softdevice Assertion with active timeslot API: Infinite retransmission of received package

RE: Softdevice Assertion with active timeslot API: Infinite retransmission of received package

Hung Bui — Fri, 24 Nov 2017 15:10:32 GMT

@m.wagner: You can of course do that, but we utilize the SHORT so that the timing would be better and less work for the CPU.

Usually in an assertion, we will try to reset the chip. If you want to stay in the assert handler, I would suggest you can think of disabling the radio in the assert handler ?

RE: Softdevice Assertion with active timeslot API: Infinite retransmission of received package

m.wagner — Fri, 24 Nov 2017 10:43:29 GMT

@HungBui Thanks. I'm pretty sure the SHORTS-Register-setting is the actual reason it happens, as I use ESB with ACK and the DISABLED_TXEN bit is set in the SHORTS register. The SHORTS-register would actually get reconfigured in the interrupt-routine but the routine probably won't get called when the softdevice asserts, so the RADIO transmits infinitely...

I just tested this again and realised that the issue actually exists in the unpatched version of nrf_esb, too. So it is reproducible using the example you uplodaed in the post I linked to.

It looks like it would make sense to have TXEN only be called from the interrupt routine instead of having it in the SHORTS register?

EDIT: I just did that and it seems to work fine so far.

RE: Softdevice Assertion with active timeslot API: Infinite retransmission of received package

Hung Bui — Fri, 24 Nov 2017 10:04:22 GMT

It could be difficult to tell what happens exactly when assertion occurs. Especially, there is a requirement that the application have to stop all peripherals before the timeslot finishes.

Which state the softdevice was when you halt the CPU ? it's advertising or in a connection ? Do you use any ACK in your ESB application ?

Could you check the SHORT and PPI that connect to the RADIO ? I suspect these automation channel actually cause the infinite transmitting.