BLE conflict with UART

[Portilha]

Hello everyone,

I am currently using Nordic NRF5340-DK board for development and I have run the zephyr UART driver sample that works an echo bot. This sample works fine for any UART that I configure, however when I add Bluetooth configuration to my proj.conf (CONFIG_BT=y), the sample seems to stop working as nothing is printed on the terminal.

Can you tell me if this behaviour is normal or how to solve it?

Best regards. 

[Portilha]

I will leave here my overlay for UART2:

&uart2 {

status = "okay";

current-speed = <115200>;

pinctrl-0 = <&uart1_default>;

pinctrl-1 = <&uart1_sleep>;

pinctrl-names = "default", "sleep";

};

And the initial proj.conf that makes the UART work for this sample:

CONFIG_GPIO=y

CONFIG_SERIAL=y

CONFIG_UART_INTERRUPT_DRIVEN=y

[dejans]

Hi,

I have tried this myself and could not reproduce your issue in NCS v2.8.0. I built the echo bot sample for nrf5340dk/nrf5340/cpuapp/ns board target. Here is the result when I added CONFIG_BT=y in the prj.conf:


After you see prompt "Tell me something and press enter:" you can just start typing anything on the next line. When you finish typing press "Enter" on your keyboard and you will get output "Echo: <whatever_you_typed>. Please note that what you type will not be visible to you before you press Enter.

Best regards,
Dejan

[Portilha]

From your logs, it seems that you are using the USB virtual COM. I am using UART1 pins (P1.0 and P1.1), and an FTDI. Can you reproduce this test scenario?

[dejans]

Hi,

Portilha said:

Can you reproduce this test scenario?

Unfortunately, I cannot do this at the moment. I am out of the office.

Please note that due to holiday season, delayed replies can be expected. I expect to get back to you during second week of January 2025. 

Best regards,
Dejan

[dejans]

Hi,

If you use UART1 pins (P1.0 and P1.1) you should see TF-M log as these pins can be used to take the output from cpunet. This can be seen in nrf5340dk_nrf5340_cpunet-pinctrl.dtsi. However, if you want to send and echo commands you should connect to pins that are given in nrf5340_cpuapp_common-pinctrl.dtsi. Instead of using P1.0 and P1.1, try using P0.20 (for UART TX) and P0.22 (for UARD RX). You should also connect the grounds. At the end, just open your newly created USB-serial COM port and test your echo application.

Best regards,
Dejan