nRF5340: issue with USB CDC ACM and UART driver running in parallel

RE: nRF5340: issue with USB CDC ACM and UART driver running in parallel

Sanscho325 — Wed, 20 Nov 2024 09:54:43 GMT

Hi,

I have the same problem, was a solution found here?

Sincerely,
Sanscho

RE: nRF5340: issue with USB CDC ACM and UART driver running in parallel

Sigurd Hellesvik — Wed, 29 Nov 2023 15:51:22 GMT

Hi,

I will continue to help with this case.

I tried to run your sample with nRF Connect SDK v1.9.1, but got no logs from the normal port on my nRF5340DK.

Did I misunderstand something here?

RE: nRF5340: issue with USB CDC ACM and UART driver running in parallel

bojan — Sat, 25 Nov 2023 11:30:38 GMT

Hello, ovrebekk .

Sorry for the late reply from my side.

Attached you can find the part of the project that you can use to explore the conflict between regular UART and virtual CDC ACM UART. We used nRF5340-DK for testing.

If in the prj.conf file the following lines are set to =n:

#BME280
CONFIG_USE_BME280=n

#USB transfer
CONFIG_USB_DEVICE_STACK=n

virtual CDC ACM UART will be disabled and regular UART will work as expected.

If the above lines are set to =y (virtual CDC ACM UART enabled), the regular UART will not work.

uart_callback_set() function will return 134 (ENOTSUP).

Please let me know if you need anything else from my side. Thanks in advance for taking a look into the codebase and let us know your opinion.

Sincerely,
Bojan.

devzone.nordicsemi.com/.../cpuapp.zip

RE: nRF5340: issue with USB CDC ACM and UART driver running in parallel

ovrebekk — Thu, 16 Nov 2023 15:09:59 GMT

Hi Bojan

Any chance you can share your example with me so I can try to reproduce the issue on my end?

If so, please just zip the project folder and attach it to your reply.

If you don't want to share your code in a public case just let me know, and I can make the case private.

Best regards
Torbjørn

RE: nRF5340: issue with USB CDC ACM and UART driver running in parallel

bojan — Wed, 15 Nov 2023 18:59:30 GMT

Hello, ovrebekk .

Thanks for your feedback.

uart_dev is installed the following way:

    uart_dev =  device_get_binding(DT_LABEL(DT_NODELABEL(uart3)));
	if (uart_dev == NULL) {
		LOG_ERR("Could not find  %s!\n\r",DT_LABEL(DT_NODELABEL(uart3)));
        return -1;		
	}

    ret = uart_callback_set(uart_dev, &uart_cb, NULL);
    if (ret != 0) {
		LOG_ERR("uart_callback_set: %d", ret);
        return ret;
	}

On the other side, here is the part of CDC ACM UART initialization:

uart_irq_callback_user_data_set(dev, interrupt_handler, NULL);

dev = DEVICE_DT_GET_ONE(zephyr_cdc_acm_uart);
if (!device_is_ready(dev)) {
	LOG_ERR("CDC ACM device not ready");
	return;
}

ret = usb_enable(NULL);
if (ret != 0) {
	LOG_ERR("Failed to enable USB");
	return;
}

CDC ACM UART is using interrupt-driven UART. Should I have the following line in the prj.conf:

CONFIG_UART_INTERRUPT_DRIVEN=y

I don't have it at the moment.

Sincerely,
Bojan.

RE: nRF5340: issue with USB CDC ACM and UART driver running in parallel

ovrebekk — Mon, 13 Nov 2023 22:01:07 GMT

It should be possible to combine regular UART's with virtual CDC ACM UART's at the same time.

Is there any chance that the uart_dev device could be the CDC ACM UART?
The CDC ACM driver does not support the ASYNC API, and will return ENOTSUP if you try to enable the callback.

How is uart_dev initialized?

Best regards
Torbjørn