Serial port library - two instances

[Bard]

Hi

I'm using SDK version15.2 and SD on a custom board based on nRF52840.

The board has two serial ports, and I want to use both independently. Using the Serial Port Library Example with two UARTEs example: https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.sdk5.v13.0.0%2Fserial_example.html and modifying it to use NRF_SERIAL_MODE_IRQ and custom pin numbers (different for the two ports), I have this code:

static void serial_cb(struct nrf_serial_s const *p_serial, nrf_serial_event_t event);
static void serial1_cb(struct nrf_serial_s const *p_serial, nrf_serial_event_t event);

NRF_SERIAL_DRV_UART_CONFIG_DEF(m_uart0_drv_config,
                      RX_PIN_NUMBER, TX_PIN_NUMBER,
                      RTS_PIN_NUMBER, CTS_PIN_NUMBER,
                      NRF_UART_HWFC_DISABLED, NRF_UART_PARITY_EXCLUDED,
                      NRF_UART_BAUDRATE_115200,
                      UART_DEFAULT_CONFIG_IRQ_PRIORITY);

NRF_SERIAL_DRV_UART_CONFIG_DEF(m_uart1_drv_config,
                      RX1_PIN_NUMBER, TX1_PIN_NUMBER,
                      RTS1_PIN_NUMBER, CTS1_PIN_NUMBER,
                      NRF_UART_HWFC_DISABLED, NRF_UART_PARITY_EXCLUDED,
                      NRF_UART_BAUDRATE_115200,
                      UART_DEFAULT_CONFIG_IRQ_PRIORITY);

#define SERIAL_FIFO_TX_SIZE 100
#define SERIAL_FIFO_RX_SIZE 100

NRF_SERIAL_QUEUES_DEF(serial_queues, SERIAL_FIFO_TX_SIZE, SERIAL_FIFO_RX_SIZE);
NRF_SERIAL_QUEUES_DEF(serial1_queues, SERIAL_FIFO_TX_SIZE, SERIAL_FIFO_RX_SIZE);

#define SERIAL_BUFF_TX_SIZE 1
#define SERIAL_BUFF_RX_SIZE 1

NRF_SERIAL_BUFFERS_DEF(serial_buffs, SERIAL_BUFF_TX_SIZE, SERIAL_BUFF_RX_SIZE);
NRF_SERIAL_BUFFERS_DEF(serial1_buffs, SERIAL_BUFF_TX_SIZE, SERIAL_BUFF_RX_SIZE);

NRF_SERIAL_CONFIG_DEF(serial_config, NRF_SERIAL_MODE_IRQ, &serial_queues, &serial_buffs, serial_cb, NULL);
NRF_SERIAL_CONFIG_DEF(serial1_config, NRF_SERIAL_MODE_IRQ, &serial1_queues, &serial1_buffs, serial1_cb, NULL);

NRF_SERIAL_UART_DEF(serial_uart, 0);
NRF_SERIAL_UART_DEF(serial1_uart, 1);

When I'm initializing the serial ports with this code:

    err_code = nrf_serial_init(&serial_uart, &m_uart0_drv_config, &serial_config);
    APP_ERROR_CHECK(err_code);
    err_code = nrf_serial_init(&serial1_uart, &m_uart1_drv_config, &serial1_config);
    APP_ERROR_CHECK(err_code);

... Fatal error ! ... or more specific "NRFX_ERROR_INVALID_STATE"  originating from nrfx_uart_init() in nrfx_uart.c. examining the function it enters these statements:

    if (p_cb->state != NRFX_DRV_STATE_UNINITIALIZED)
    {
        err_code = NRFX_ERROR_INVALID_STATE;
        NRFX_LOG_WARNING("Function: %s, error code: %s.",
                         __func__,
                         NRFX_LOG_ERROR_STRING_GET(err_code));
        return err_code;
    }

So it seems that uart is already initialized? why? Any ideas what can be wrong?

[Susheel Nuguru]

with mode set as IRQ, put a breakpoint at nrfx_uart.c and the code in debug mode.

Check if the breakpoint is hit with the initialization of the same instance of uart twice. You will be able to understand why this happens if you look at the call stack.