UART transaction trigger app_error_handler

[MH]

Hi,

I'm using the 3rd generation of nRF51822 with S110 v8.0.0 and the SDK 10.0. In my application i'm using the uart core to communicate with the external device. I'm using the following code to initialize the UART core

void UART_INIT (void)
{
		
    uint32_t                     err_code;
    const app_uart_comm_params_t comm_params =
    {
        UART_RX_PIN_NUMBER,
        UART_TX_PIN_NUMBER,
        0,
        0,
        APP_UART_FLOW_CONTROL_DISABLED,
        false,
        UART_BAUDRATE_BAUDRATE_Baud57600
    };

    APP_UART_FIFO_INIT( &comm_params,
                       UART_RX_BUFFER_SIZE,
                       UART_TX_BUFFER_SIZE,
                       uart_event_handle,
                       APP_IRQ_PRIORITY_LOW,
                       err_code);
    APP_ERROR_CHECK(err_code);		   		  		  		   		
}	

The application works for a while (send and receive successfully) and suddenly it trigger the app_error_handler function.

The app_error_handler indicate that the error comes from nrf_drv_uart.c in line 0x100.

When i check the line 0x100 i see that the

ASSERT(m_cb.state == NRF_DRV_STATE_INITIALIZED);

line is causing the problem. i debug the program and noticed that the value of m_cb.state is 0x54 at the time that error is occurred.

I have no idea how to solve the problem.

Please let me know if any more information you need to assist me to solve the problem.

[Susheel Nuguru]

1. It must be memory corruption as mb_state cannot have value 0x54. It If you are using Keil, then create a breakpoint on write access to mb.state in nrf_drv_uart.c. You will then know what has changed this value.

2. Check to see if this behavior is same if you do not use softdevice (I mean disable the softdevice and run your application).

[Susheel Nuguru]

you are using it right -O0. You now were able to see that strcat was writing to m_cb.state. Can't you see why one of the string pointers was pointing to this part of memory? Are you using pointers instead of addresses to array? Please post some code here for the string initialization and strcat context