nRF52 DK and UART Example on PC

[Mark]

I opened, compiled, and uploaded the UART example on my nRF52-DK board using KEIL IDE. I use either CoolTerm or RealTerm on my PC. When I open the Terminal program I can see COM port 8 connected to my nRF52-DK. I followed this setup and got connected:

Baud rate: 115.200

8 data bits

1 stop bit

No parity

HW flow control: RTS/CTS

However I don't see "Start:" nor 'Exit!' when I enter q/Q.

Aren't I supposed to connect to the Terminal program through the same USB port as for programming nRF52-DK board? Or am I supposed to use another port with an external device to get connected to Terminal program?

Thanks in advance

[Ole Bauck]

The setup looks correct. The serial communication is through the same usb interface. Are you sure the code is running and calling printf("\n\rStart: \n\r")?

[Mark]

I can see part of the code is:

 #ifndef ENABLE_LOOPBACK_TEST
    printf("\n\rStart: \n\r");

    while (true)
    {
        uint8_t cr;
        while(app_uart_get(&cr) != NRF_SUCCESS);
        while(app_uart_put(cr) != NRF_SUCCESS);

        if (cr == 'q' || cr == 'Q')
        {
            printf(" \n\rExit!\n\r");

            while (true)
            {
                // Do nothing.
            }
        }
    }
#else

    // This part of the example is just for testing the loopback .
    while (true)
    {
        uart_loopback_test();
    }
#endif

I'm not using bluetooth, but do I need a softdevice on the chip as well?

I started debugging, and the code is running. I used LEDs to see how far I get, and it seems the code runs as it should, but I don't see the printing messages on the terminal!

Any Idea?

[Mark]

After a lot of searching and trying different methods and debugging, I finally figured out the problem. All I had to do was to download the latest J-Link software and install it replacing the older version.

I originally had V5.10d, and once updated to V5.12d it fixed the problem!

I can use printf() without any problem anymore.

[KingKarl237]

It does work with PUTTY here. Note that in the Example the standard setting is UART_BAUDRATE_BAUDRATE_Baud38400

[Ole Bauck]

You don't need the SoftDevice for this example. Probably something is wrong at the other end. You will have to probe the lines (f.ex. CTS) to see if they have the correct value and the data is sent.