nrf52 uarte receive timeout

RE: nrf52 uarte receive timeout

NewtoM — Wed, 03 Aug 2016 12:42:10 GMT

I can confirm that Ole's recommendation works. :)

RE: nrf52 uarte receive timeout

Sheikh_Khaled_Dubai — Tue, 26 Jul 2016 19:12:53 GMT

yes it would be awesome to implement that soon in the SDK driver !!!! we are planning to work in the future projects more with Nordic

RE: nrf52 uarte receive timeout

NewtoM — Thu, 21 Jul 2016 13:37:38 GMT

OK, it seems I got the first part (counter reset on RX) done. However, I used RTC0 (at 32768 Hz) instead of a timer. At this rate I get a tick at every ~31 μs, plus there is a delay for clearing the counter up to 46 μs based on the documentation. That adds up to a time in which about 7 characters could have been received at 1Mbps. So if during this period of time no more characters were received it seems reasonable to me to call nrf_drv_uart_rx_abort(), fetch the data of length nrf_uarte_rx_amount_get() from the buffer upon the NRF_DRV_UART_EVT_RX_DONE event, and call nrf_drv_uart_rx(..) to re-engage RX. Is that right?

RE: nrf52 uarte receive timeout

NewtoM — Thu, 21 Jul 2016 10:35:50 GMT

Thanks! This is what I was looking for.

RE: nrf52 uarte receive timeout

hcr — Thu, 21 Jul 2016 10:31:43 GMT

Newtom: There is a nrf_drv_uart_rx_abort command which does what you want, stops the reception and gives you the received bytes (in the same event as when the dma buffer is full)

infocenter.nordicsemi.com/index.jsp

RE: nrf52 uarte receive timeout

hcr — Thu, 21 Jul 2016 09:26:49 GMT

No, sorry not any time soon. But if I remember correctly there are examples from nordic for all the parts you need.

RE: nrf52 uarte receive timeout

NewtoM — Thu, 21 Jul 2016 08:21:53 GMT

Hi hcr, will you have access to the code soon or I better shouldn't wait for that? Thx!

RE: nrf52 uarte receive timeout

hcr — Wed, 20 Jul 2016 20:45:26 GMT

Thanks, adding this functionality to the SDK driver would be very useful!

RE: nrf52 uarte receive timeout

hcr — Wed, 20 Jul 2016 20:44:08 GMT

Hi,

I implemented a solution similar to what Ole proposes below. Unfortunately I don't have the code available at this time so I cannot help you with the details.

RE: nrf52 uarte receive timeout

NewtoM — Wed, 20 Jul 2016 19:18:58 GMT

Ole, I still would have two questions to your solution for the meantime. First, by flushing the DMA buffer you mean discarding the bytes in the non-full buffer or fetching them? If the latter, how to do that? Second, can you please explain (or at least give a good pointer to the documentation on) how to connect the GPIOTE IN event to the UARTE RX pin to reset a timer? Thank you!

RE: nrf52 uarte receive timeout

NewtoM — Tue, 19 Jul 2016 08:52:19 GMT

That's great news! I am looking forward to using that.

RE: nrf52 uarte receive timeout

Ole Bauck — Tue, 19 Jul 2016 08:32:26 GMT

Hi,

Unfortunately, there is no way to do this only with the UARTE peripheral.

A solution is to connect GPIOTE IN event to the UARTE RX pin and reset a timer when there is any activity on the pin. If the timer reaches a certain timeout, you know that there have been no data received for that time and you can flush the DMA buffer.

We are working on implementing this in the SDK driver.

Ole

RE: nrf52 uarte receive timeout

NewtoM — Mon, 18 Jul 2016 20:51:43 GMT

The issue hcr was interested in is exactly my issue now. Did you find any feasible solution?

RE: nrf52 uarte receive timeout

FormerMember — Wed, 07 Oct 2015 15:18:36 GMT

I couldn't find any way to do this with only the UART peripheral (a pity). I guess one of the timers need to be used in conjunction with the UART peripheral.