LIBUARTE on ble_app_uart with DMA

[Bar1]

Hi All,

I have 2 boards nrf52840 pc10056 and I need to run ble_app_uart using LIBUARTE with DMA in order to obtain a more robust uart communication

I would like to use an uart DMA that will work in background saving the byte received in a buffer (fixed length) and once that it is full having an interrupt where I can check this buffer and send it to the central unit.

Is there any easy way to set  everything up and change the code of ble_app_uart? Any suggestion??

Thanks

[Simonr]

Hi 

You might be seeing a SoftDevice assert because you won't be able to step debug the application code when the SoftDevice is enabled. If you want to step through the code you need to use what is called Monitor Mode Debugging that you can read here. You need to get a return value from sd_ble_gatts_hvx for us to be able to see what exactly goes wrong.

Are you employing double buffering in your application? I found this thread which explains this quite well. Could you try implementing something like that, and fill one RX buffer while the other one is transferring and emptying?

Best regards,

Simon

[RoyCreemers]

Please check the following topic about libuarte:

https://devzone.nordicsemi.com/f/nordic-q-a/48321/using-libuarte-during-flash-operations

We also had some issues with libuarte in combination with soft device. There seemed to be some issues in the code. Nordic provided some patches for this code in this topic.

[Bar1]

Hello,

I have changed the priority interrupt in libuarte_async.c from 1 to 5 and it now works. Work means that it does not stop anymore sending data from the peripheral to the central. The problem now is how these data are sent, because the buffer that I receive from the UART (peripheral side) is changing continuously length.....even if the packet length is fixed and the buffer has same size or bigger (I tried every thing).

Today I saw the post of  RoyCreemers, I thought could be same problem so I did what was indicated there....result is that it does not work.

Another problem (very big actually) is that the board works just in debug mode. The weird thing is that even the experiment_libuarte that is in SDK_15.3 does not work in modality DEBUG (On segger embedded studio), but just on Release. Very strange stuff. I think I give up, I cannot spend more time on it even because every day I discover a new bug.

Anyway thanks a lot for your help and your time. 

Regards

[Jonathan_NB]

Hi Barl,

Would you be able to share with me your LIBUARTE on ble_app_uart with DMA example? 

Best regards,
Jonathan