things allow/not allowed to call from callbacks NRF52/S132

RE: things allow/not allowed to call from callbacks NRF52/S132

Petter Myhre — Fri, 02 Dec 2016 11:14:59 GMT

I'm not sure why you can't print floats, maybe add a separate question? I'm not sure what kind of overview you are after, but this Section in the SoftDevice specification should be examined at least.

RE: things allow/not allowed to call from callbacks NRF52/S132

peter — Thu, 01 Dec 2016 13:48:51 GMT

Hi Petter, your comments so far helped a lot. summarizing again:

issue #1 is still the same

issue #2 for TWI I changed the priority to LOW (just took the HIGH prio over from the TWI example in the SDK without looking at it too closely) -> this seems to work a lot better

issue #3: ok, I found it and understood it, so no issue anymore.

issue #4: now that the TWI callback works correctly, if I do NRF_LOG_INFO("%f",some_float_var), it will hang right there, unless I add linker option -u _printf_float, then it will always print 0.000000. I saw the macros for outputting a float as two integers, is this the recommended option?

as for the overview, it wasn't completely clear to me from the docs on how those IRQ levels behave and what exactly is possible. I know that the docs mentioned several things, but it wasn't completely clear. I think I understand the IRQ levels now and my mistake with TWI there, but as for issue #1 and #4, it's unclear to me how IRQ levels that I control would influence that.

RE: things allow/not allowed to call from callbacks NRF52/S132

Petter Myhre — Thu, 01 Dec 2016 13:00:25 GMT

I'm not sure what kind of overview you mean, but you cannot call SoftDevice API from APP_IRQ_PRIORITY_HIGH (1). This is because every SoftDevice API call is triggering SVC interrupt and this interrupt is on level 2 (lower than application high level).

You can call SoftDevice (including sd_nvic_... functions) from APP_IRQ_PRIORITY_LOW (3) and main context.

The behavior you describe sounds really strange. What do you mean by one advertisment? One advertising packet? Then it would be very difficult for a central to connect...?

RE: things allow/not allowed to call from callbacks NRF52/S132

peter — Thu, 01 Dec 2016 12:50:15 GMT

Hi! that was APP_IRQ_PRIORITY_HIGH, is there a good overview what kind of things need which priorty?

Also something that might be related: if I turn on logging (compile flag NRF_LOG_ENABLED=1), then there will be exactly one advertisement, and nothing else. Also e.g. the app_timer does not work while advertising, but as soon as somebody connects, it will start working. Any ideas what all if this could be?

RE: things allow/not allowed to call from callbacks NRF52/S132

Petter Myhre — Thu, 01 Dec 2016 11:46:45 GMT

For 2, what interrupt priority have you configured the driver to use?