One of nRF5340 audio DK not working at 1M hci uart

[sridhar j]

I have used nrf5340 audio DK with nrf\applications\nrf5340_audio\bin\ble5-ctr-rpmsg_3251.hex in net core and zephyr\samples\bluetooth\hci_uart in app core directly after receiving board.

In hci uart project configuration, we have tried 1M,115200 baudrates and flashed into 4 boards. Out of which one board is not working.

Please help us in bringing up that board.

Thanks,

Sridhar

[Priyanka]

Hi Sridhar,

Do you have 4 nRF5340 Audio DKs? Are all the other 3 boards working well? Is there any error that occurs in the faulty board ? 

Have you tried resetting the board and also check the USB cable connected to it?

Best Regards,

Priyanka

[sridhar j]

Hi Priyanka,

There is no error in faulty board as I see.

All other 3 working fine.

Yes I have 4 DKs.

USB cable and entire setup same as in other 3 working boards

[Priyanka]

Hi Sridhar,

When you say that the DK is not working, could you provide more details regarding this? It can help figure out the problem.

Do you have any extra connections on this DK or have you done any changes from the rest?

-Priyanka

[sridhar j]

1. Flash network core: nrfjprog --program nrf\applications\nrf5340_audio\bin\ble5-ctr-rpmsg_3251.hex --chiperase --coprocessor CP_NETWORK -r

2. Change to uart1 from uart0

nrf\boards\arm\nrf5340_audio_dk_nrf5340\nrf5340_audio_dk_nrf5340_cpuapp_common-pinctrl.dtsi

&pinctrl {

    uart1_default: uart1_default {

        group1 {

            psels = <NRF_PSEL(UART_TX, 1, 9)>,

                <NRF_PSEL(UART_RTS, 1, 10)>;

        };

        group2 {

            psels = <NRF_PSEL(UART_RX, 1, 8)>,

                <NRF_PSEL(UART_CTS, 1, 11)>;

            bias-pull-up;

        };

    };

    uart1_sleep: uart1_sleep {

        group1 {

            psels = <NRF_PSEL(UART_TX, 1, 9)>,

                <NRF_PSEL(UART_RX, 1, 8)>,

                <NRF_PSEL(UART_RTS, 1, 10)>,

                <NRF_PSEL(UART_CTS, 1, 11)>;

            low-power-enable;

        };

    };

};

3. Setting uatrt1 pins, baudrate to 1M

zephyr\samples\bluetooth\hci_uart\boards\nrf5340_audio_dk_nrf5340_cpuapp.overlay

&uart1 {

    compatible = "nordic,nrf-uarte";

    status = "okay";

    current-speed = <1000000>;

    pinctrl-0 = <&uart1_default>;

    pinctrl-1 = <&uart1_sleep>;

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

    hw-flow-control;

};

&i2c1 {

    compatible = "nordic,nrf-twim";

    status = "disabled";

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

};

/ {

    chosen {

        zephyr,console = &uart0;

        zephyr,shell-uart = &uart0;

        zephyr,uart-mcumgr = &uart0;

        zephyr,bt-mon-uart = &uart0;

        zephyr,bt-c2h-uart = &uart1;

    };

    gpio_fwd: nrf-gpio-forwarder {

        compatible = "nordic,nrf-gpio-forwarder";

        status = "disabled";

        uart {

            gpios = <&gpio1 9 0>, <&gpio1 8 0>, <&gpio1 11 0>, <&gpio1 10 0>;

        };

    };

};

3. zephyr\samples\bluetooth\hci_uart

west build ./ -b nrf5340_audio_dk_nrf5340_cpuapp -p

west flash

Now giving commands from our host at 1M baudrate to nordic, hci command response is not coming to host

[Priyanka]

Hi Sridhar,

Could you lower the baudrate from 1Mbps to 115200bps and give a trial for all 4 DKs? Also, which DK version do you have for all 4 DKs?

-Priyanka

[sridhar j]

Yes same issue on 115200.

DK version is 1.0.0 2022.10. 2 are working and 1 is not working.

[Priyanka]

The v1.0.0 revision has some issues when working at 1Mbps and hence 115200bps is used for application log. You had mentioned that you have 4 DKs right? So just the one is not working? even at 115200bps?

-Priyanka