How best to interface the nRF52832 module (BMD300) using an ATMEL microcontroller ?

[Ruscon]

I have the BMD-300 series evaluation board and I am able to program the various examples supplied from Nordic and communicate using the Nordic smartphone apps. I propose to use the development board to program a BMD300 module to act as a simple UART and mount this on a custom PCB to interface with a ATMEGA256A3BU controller.

Once programmed, is it possible to treat the BMD300 device as a dumb UART and communicate with the device using Rx and Tx lines alone ? I would simply forward all received data to the Tx port of the BMD300. Is this a reasonable approach or will it be necessary to have substantial support for initializing the device on startup ?

 

[Karl Ylvisaker]

Hello,

Yes, this is possible, and it is exactly what the Nordic Peripheral UART service does.
It forwards anything it receives over the BLE NUS service to its UART, and anything it receives over UART to its BLE NUS service.
Please give this a try, and let me know if you should encounter any issues or questions when doing so! :) 

Best regards,
Karl

[Ruscon]

Hi Karl,

thanks so much for your quick response, I will give this a try and report back if any issues arise ;-)

[Ruscon]

Hi Karl,

I am running the application in Linux Mint:

Linux Mint-MS-7C83 5.4.0-91-generic #102-Ubuntu SMP 
Fri Nov 5 16:31:28 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

I have selected the ble_app_uart_pc10040e_s112 project, compiled and downloaded to the BMD300_EVAL development board. I have configured JLink as described in the "Getting stared with NRF5SDK and SES" notes and JLink appears responsive within terminal. The JLink web control panel continually reports a lost connection with JLink DLL, not sure if this is a problem or not ...

I am connecting to the development board using the Nordic nRF Toolbox  UART application which connects without problems. From within the mobile app I attempt to send text which subsequently appears on the Output screen of the app, however I do not see any received text within the SES debugger, neither on the RTT client or the debug terminal or the terminal emulator. 

Can you advise firstly on the JLink web control panel issue and also suggest a method by which I can detect incoming text to the BMD300_eval board ?

[Karl Ylvisaker]

Hello,

Ruscon said:

I am connecting to the development board using the Nordic nRF Toolbox  UART application which connects without problems. From within the mobile app I attempt to send text which subsequently appears on the Output screen of the app, however I do not see any received text within the SES debugger, neither on the RTT client or the debug terminal or the terminal emulator. 

Do I understand it correctly that everything but the output from the device seems to work as expected?
The Nordic UART example will be default output the data received over BLE through its UART, so to see the text you have sent it you will have to use a serial terminal/monitor on your computer, instead of the RTT Viewer or SES Debug terminal.
Please try to use a serial terminal like PuTTy or similar to view the output, and let me know if you should encounter any issues or questions! :) 

Best regards,
Karl

[Ruscon]

Hi Karl,

yes, the application appears to be working correctly and I assumed that serial data sent from the phone app would appear in a debug screen or on the terminal hosting the clientRTT app. I will use puTTy as suggested and let you know how I go. Thanks for the support, it is really appreciated !

[Karl Ylvisaker]

Hello,

Ruscon said:

Thanks for the support, it is really appreciated !

No problem at all, I am happy to help! :) 

Ruscon said:

yes, the application appears to be working correctly and I assumed that serial data sent from the phone app would appear in a debug screen or on the terminal hosting the clientRTT app. I will use puTTy as suggested and let you know how I go.

Great!
The default behavior of the BLE Nordic UART application is to use the RTT output for the logger, since the UART is being used by the application to output the messages received over BLE. Don't hesitate to let me know if you should encounter any issues or questions while working with this!

Best regards,
Karl

[Ruscon]

Hi Karl,

everything is working now, used puTTy as suggested and was able to transfer text successfully ;-)

I still have the problem with the J-Link web panel advising constant re-connection with the JLink DLL however this did not prevent normal operation of the nRF52832 UART app. I have contacted JLink support to see if a solution exists for this behaviour.

Once again Karl, thanks for your support, it is much appreciated.

regards,

Russell

[Karl Ylvisaker]

Hello,

Ruscon said:

everything is working now, used puTTy as suggested and was able to transfer text successfully ;-)

Ruscon said:

Once again Karl, thanks for your support, it is much appreciated.

It is no problem at all, Russell - I am happy to help! :) 
I am glad to read that everything works as expected now!

Ruscon said:

I still have the problem with the J-Link web panel advising constant re-connection with the JLink DLL however this did not prevent normal operation of the nRF52832 UART app. I have contacted JLink support to see if a solution exists for this behaviour.

Hmm, that does indeed sound strange - have you tried updating/reinstalling the command line tools/J-Link tools, to see if that makes any difference?

Best regards,
Karl