Custom nRF21540 DTM UART pins

RE: Custom nRF21540 DTM UART pins

Kenneth — Tue, 19 Apr 2022 12:00:43 GMT

Pin P1.00 is <32>.

Kenneth

RE: Custom nRF21540 DTM UART pins

Kenneth — Tue, 19 Apr 2022 11:59:19 GMT

Hello,

If you haven't already I suggest to check out:
https://academy.nordicsemi.com/courses/nrf-connect-sdk-fundamentals/

Once you are familiar with devicetree and how to make overlay files, then you will be able to modify or add the nrf21540:
https://github.com/nrfconnect/sdk-zephyr/blob/main/boards/arm/nrf21540dk_nrf52840/nrf21540dk_nrf52840.dts#L113

Kenneth

RE: Custom nRF21540 DTM UART pins

rikhard — Tue, 19 Apr 2022 11:45:21 GMT

Update: I managed to install toolchains, built the direct_test_mode app and verified that the pins P0.06 and P0.08 and for BLE 2-wire communication. I was able to run tests against Anritsu MT8852B via FTDi -cable.

However, then I needed to change the GPIO pins from default to something else. I changed them to P0.25 and P0.06 and that change works after I committed the changes to overlay file as per https://devzone.nordicsemi.com/nordic/b/archives/posts/nrf-connect-sdk-tutorial---part-3-temporary

But if I used P1.00 (overlay file configuration as pasted below), the communication between DUT and tested did not happen.

How can I configure P1.00 as serial?

I try to run this with nRF21540db board. My custom board does not have other GPIOs available than P1.00 and P0.25.

&uart0 {
	status = "okay";
	current-speed = <19200>;
	tx-pin = <100>;
	rx-pin = <25>;
	rts-pin = <5>;
	cts-pin = <7>;
};