FDS SDK13 : Failure to initialise from time to time

RE: FDS SDK13 : Failure to initialise from time to time

MartinBL — Mon, 31 Jul 2017 13:42:54 GMT

I suppose the documentation can always be improved.

RE: FDS SDK13 : Failure to initialise from time to time

RichieJH — Mon, 31 Jul 2017 09:37:14 GMT

Ok I see, perfectly logical. This is quite a key point but doesn't seem to be drawn out very well in the demos nor in the FDS documentation. So what I did was raise the write_flag in the init step, so the next call had to wait until the flag cleared.

static void my_fds_evt_handler(fds_evt_t const * const p_fds_evt)
{
    switch (p_fds_evt->id)
    {
        case FDS_EVT_INIT:
            if (p_fds_evt->result != FDS_SUCCESS)
            {

                APP_ERROR_CHECK(p_fds_evt->result);
                // Initialization failed.
            }
            if (p_fds_evt->result == FDS_SUCCESS)
            {
                write_flag=1;

            }
            break;
	case FDS_EVT_WRITE:
            if (p_fds_evt->result == FDS_SUCCESS)
            {
		write_flag=1;
            }
            break;
        default:
            break;
    }
}

On a quick test this seems to have solved the problem entirely. Surprised it's not suggested as standard practice just like the flag on the other elements of FDS?

RE: FDS SDK13 : Failure to initialise from time to time

MartinBL — Mon, 31 Jul 2017 06:15:08 GMT

Hi,

Are you waiting for the FDS_INIT callback after calling fds_init()? It sounds like you are trying to do FDS operations before the module is porperly initiated. Refer to the FDS documentation:

Initialization, like all other operations in FDS that involve writing or erasing flash memory, is an asynchronous operation.

RE: FDS SDK13 : Failure to initialise from time to time

RichieJH — Sun, 30 Jul 2017 10:57:43 GMT

UPDATE:

After much searching I got it to work by adding nrf_delay_ms(2) between fds_init() and fds_test_find_and_delete(). Then it began working. Out of interest I then commented out the nrf_delay_ms(2) and it still works! I'll keep an eye on it since it seems a little unstable.

UPDATE 2:

During the course of the day I notice that FDS will fail from time to time. At one stage it failed even when the delays was 2ms, but changing it to 10ms solved it. It seems in my case there can be a delay in FDS initing that needs to be taken into account. I am not sure if this is expected behaviour or not, but that's my observation.