Problem sending 6 bytes to multiple services using sd_ble_gatts_hvx

RE: Problem sending 6 bytes to multiple services using sd_ble_gatts_hvx

Renix — Tue, 25 Apr 2017 13:26:44 GMT

Petter,

I think the while (!spi_xfer_done) { __WFE(); } is causing problems. I removed the __WFE(); inside of the timer update, but still no go.

The only way I could get SPI to function correctly, was to leave it in the main loop, and place an if() around it, so set a flag inside the timer event, so the main() loop will the do the SPI transfer.

It works, so all I can say is unless the SPI was stopped, the asynchronous SPI reads with the Timer 1sec interrupt, does not work.

Thanks.

RE: Problem sending 6 bytes to multiple services using sd_ble_gatts_hvx

Petter Myhre — Tue, 25 Apr 2017 06:50:09 GMT

I'm not exactly sure what is going on here, and even if you shared your code it would be a bit difficult to test it. Can't you just have a 2, 3 or 5 second timer and start the SPI transfer from the timer? And when the SPI transaction is complete you update the characteristics?

RE: Problem sending 6 bytes to multiple services using sd_ble_gatts_hvx

Renix — Tue, 25 Apr 2017 03:23:19 GMT

I still have problems with updating characteristics to quickly. If I call the three (3) characteristic updates in the main() loop, it works.

our_termperature_characteristic_update(&m_our_service, &testchar[12]);
sr2_termperature_characteristic_update(&m_sr2_service, &testchar[6]);
sr3_termperature_characteristic_update(&m_sr3_service, &testchar[0]);

If I call it from the static void timer_timeout_handler(void * p_context)

then the SPI info is out of sync. So it seems because SPI is updated through an interrupt, (not DMA it seems), SPI info is correct right after while (!spi_xfer_done)

But if I call my service characteristic updates from timer_timeout_handler(void * p_context) Since it is asynchronous with SPI events, I get shifted SPI info. So by the time the timer happens, SPI has updated some values, but not all.

It is still correct information, it is just shifted in the buffer, so say val[1] holds val[5] info.

The problem is that I place a nrf_delay_ms(500); in the main loop, so the updates happens very quickly. I've seen on a iPhone 4s that after a while, the screen starts flickering as updates happen.

So I need to slow the updates down, 1sec or even 5 second update rate is fine.

I saw a suggestion to uninit the SPI, but that did not seem to work.

I need a way to update every say 2 or 3 or 5 seconds, but know when SPI has the correct info.

Any help appreciated

RE: Problem sending 6 bytes to multiple services using sd_ble_gatts_hvx

Renix — Fri, 21 Apr 2017 12:23:32 GMT

I guess either stop the SPI, or only call nrf_drv_spi_transfer to update the rx_Buffer, and then update the characteristics. Thanks

RE: Problem sending 6 bytes to multiple services using sd_ble_gatts_hvx

Renix — Fri, 21 Apr 2017 12:20:39 GMT

Petter,

I believe I found the issue.

I was calling the characteristic updates from inside the 1sec timer routine.

So I think the SPI is free running, (in the main while loop) so it updates all the time.

During the time the 1sec timer interrupts, the SPI may have updated. So I moved the characteristic update calls to right after the nrf_drv_spi_transfer

FIXED!! A hack a day keeps the doctor away.

Regards

RE: Problem sending 6 bytes to multiple services using sd_ble_gatts_hvx

Petter Myhre — Fri, 21 Apr 2017 09:05:38 GMT

So you have made 3 services with one characteristic in each? What exactly fails? Do you get any error inside our_temperature_characteristic_update()? Have you tried to use the debugger to see what happens? Does the chip reset? The last code piece you included seems to me incomplete, is this on purpose?