How to use UART on nrf52832 together with Zephyr RTOS?

[Aduka_27]

Hi guys,

Does anybody know how to send the sensor data from the nrf52832 device to the terminal when it is not connected directly to the PC with USB cable. I tried with FTDI cable and connected wires to the propriety pins, but I am still not able to see anything in my Minicom terminal. Do you maybe know how can I fix this? Can I do that using UART or something else? I will appreciate a lot if you have an example to show me how can start solving this problem. Thanks a lot in advance and kind regards!!

[Vidar Berg]

Hello,

It should not be a problem to view UART data on minicom if you have a working setup. Are you using the nRF52 DK or a custom/third-party board?

FTDI cable and connected wires to the propriety pins, but I am still not able to see anything in my Minicom terminal.

 Which pins did you connect?

[Aduka_27]

I am using the nRF52dk_nRF52832 board and running the Zephyr on it. Do you maybe have the example how can I configure and use the UART communication, because I found some example but not relevant for Zephyr. Do you maybe have some example where I can see how to configure the related pins and way of communication? I used 5V, GND and Tx (P0.06) pins on my board, and 5V, GND and Rx pins on the FTDI cable.

[Vidar Berg]

Thanks for the clarification, but could you please confirm if you're using the nRF52 DK (link), or is it a different board. I'm asking because the DK board already comes with an on-board serial bridge (via the Jlink) so you don't need any external FTDI cable. To test the UART communication, you can use the simple echo sample in \ncs\zephyr\samples\subsys\console\echo. TX is connected to P0.06 by default.

Please note that supplying 5v directly may cause permanent damage to the chip. The same applies to the UART bus, the voltage must not exceed VDD+0.3V.

[Aduka_27]

I use the same nRF52 DK board as you send me in this link. But, what to do in my case when I disconnected my board from my laptop and connected the relevant pins to my emulator (which emulates the environmental power sources)? How to flash the example in that case and see the output (in my case for example output will be 2.7V)?

[Vidar Berg]

I assumed the requirement was to get UART/USB communication with your PC to work. It would be good to know what the actual purpose/goal of using an external serial bridge and power source is. You can't program the device through the UART interface unless you already have FW supporting DFU over UART running on your device.

And please make sure the voltage on the FTDI is the same as the VDD voltage going into the nRF52 so the TX and RX line doesn't exceed VDD+0.3V as mentioned earlier.