I want to change baudrate of uart at nRF52832

[PAL_fujita]

Hello,

I use the SDK15.3.0.

(nRF5_SDK_15.3.0_59ac345 -> example -> ble_peripheral -> ble_app_uart ->pca10040 -> s132 -> ses)

The default baudrate of uart is 115200bps.

I want to change baudrate to 38400bps.

I saw the following file. (sdk_config.h, nrf_uart.h, nrf52_bitfields.h, nrf52.h, etc.)

I did not understand which files need to be changed.

Please teach me how to change the boardrate of uart.

Best regards,

Toru

[cbd]

As a rule, if you are using any of the library files or example code then changes will need to be made to sdkconfig.h.

It is possible to code your project entirely without using the library code if you so wish.

[PAL_fujita]

Hi cbd-san,

Thank you for your reply.

I tried the solution from you.

But the baudrate did not change.

Can you advise me why it can not change the baudrate?

Best regards,

Toru

[cbd]

Okay.

I suspect that you may have UART enabled as well as UARTE - it is confusing I know. I believe that UART is to be legacy code support and that UARTE is the way forward.

Try checking NRFX_UART_DEFAULT_CONFIG_BAUDRATE

If you wanted to change it directly then you could use the following within your own code where you define the values for RX_PIN_NUMBER, TX_PIN_NUMBER … etc.:

static uint32_t com_UartInit(void)
{
    uint32_t err_code;
    app_uart_comm_params_t const comm_params = {
        .rx_pin_no = RX_PIN_NUMBER,
        .tx_pin_no = TX_PIN_NUMBER,
        .rts_pin_no = RTS_PIN_NUMBER,
        .cts_pin_no = CTS_PIN_NUMBER,
        .flow_control = APP_UART_FLOW_CONTROL_DISABLED,
        .use_parity = false,
#if defined(UART_PRESENT)
        .baud_rate = NRF_UART_BAUDRATE_38400
#else
        .baud_rate = NRF_UARTE_BAUDRATE_38400
#endif
    };

    APP_UART_FIFO_INIT(&comm_params, UART_BUF_SIZE, UART_BUF_SIZE,
                       com_UartEventHandler, /* Handler for UART events */
                       APP_IRQ_PRIORITY_LOWEST, err_code);

    return (err_code);
}

[PAL_fujita]

Hi cbd-san,

Sorry for my late reply.

I checked the codes along with the advice from you.

And I was able to find the wrong code.

I was able to run uart at 38400 bps.

Thank you for your support.

Best regards,

Toru