If I don't want to test RF performance through USB, how can I test NRF9160 performance through an external interface

[ychen]

Now it is the nRF9160 DK. I can test the LTE RF performance by transmitting AT commands through USB, but I also hope that I can also connect the nRF9160 through an external interface ,and how to connect and power the hardware to test the LTE RF performance. Thank you.

[Didrik Rokhaug]

Hi.

You can send AT commands over UART (this is also what happens when sending them over USB. The debugger acts as a USB <-> UART bridge).

The default pins for UART0 can be found on the backside of the DK, or in the device tree files.

Best regards,

Didrik

[ychen]

HI.

May I tell me how to connect? Now, I connected P0.28 and P0.29 through the external interface. But uart still doesn't work, why?If possible, can you give me a connection diagram.

[Didrik Rokhaug]

Yes, my apologies.

By default, the UART pins are not routed to the header, but to the debugger, which acts as a UART<->USB bridge.

To route the pins to the header instead, you need to change the firmware on the board controller. You can use the hello_world sample in Zephyr, and change the routing by adding

CONFIG_BOARD_PCA10090_UART0_VCOM=n
CONFIG_BOARD_PCA10090_UART0_ARDUINO=y

I have attached a hex file with the necessary changes. Flash it to the nRF52840 on the nRF91DK (pca10090), and you should be able to use the external interface.

uart_header.hex

[ychen]

Thank you. I will download uart_header.HEX to nRF9160DK. Is that ok?

[Didrik Rokhaug]

Yes, but make sure that the PROG/DEBUG switch (SW5) is set to "nrf52", not "nrf91".

[ychen]

Thank you ,I will try