UART hits communication error

RE: UART hits communication error

wael — Mon, 02 Oct 2017 18:24:08 GMT

Thanks Martin. But if I do that, I won't be able to communicate with the device when the UART lines are physically connected. The problem I was seeing only appears when the UART lines are not physically connected.

I retried the pull-up option and it worked.

RE: UART hits communication error

wael — Mon, 02 Oct 2017 18:22:52 GMT

I retried the pull-up option and it worked.

Changed the pull option in apply_config():

nrf_gpio_cfg_input(p_config->pselrxd, NRF_GPIO_PIN_PULLUP);

RE: UART hits communication error

MartinBL — Mon, 02 Oct 2017 09:10:13 GMT

Hi,

You can disconnect the RX pin from the UART module completely by setting the RX pin number to 0xFFFFFFFF. UART PSEL documentation.

When you init the UART you can do it like this:

const app_uart_comm_params_t comm_params =
  {
      UART_PIN_DISCONNECTED, // <- 0xFFFFFFFF
      TX_PIN_NUMBER,
      RTS_PIN_NUMBER,
      CTS_PIN_NUMBER,
      APP_UART_FLOW_CONTROL_DISABLED,
      false,
      UART_BAUDRATE_BAUDRATE_Baud115200
  };

APP_UART_FIFO_INIT(&comm_params,
                     UART_RX_BUF_SIZE,
                     UART_TX_BUF_SIZE,
                     uart_error_handle,
                     APP_IRQ_PRIORITY_LOWEST,
                     err_code);