Cann't write data to flash by using pstorage.

RE: Cann't write data to flash by using pstorage.

Stefan Birnir Sverrisson — Tue, 27 Oct 2015 15:36:42 GMT

Hi Alice

Im not sure I understand your problem.

However, the way it works under the hood is that you can only erase a whole flash page. In pstorage, you can choose to erase just a few bytes, but what happens under the hood is that the untouched data of the page is swapped out, then the whole page is erased and then the untouched data is swapped in again.

You can choose to update just certain bytes in a block by calling the pstorage_update function. What happens under the hood when you use that function is described here.

RE: Cann't write data to flash by using pstorage.

Alice — Thu, 22 Oct 2015 11:10:12 GMT

Hi Dan,

Thanks for your help.I have another peoblem.For example,I need to write two variables(A and B) to the flash in the same page.I want to just update one variable(A or B) value by using pstorage,what should I do?

Now I do it like this:Firstly,I read the value of the two variable,then update one variable(A or B) value,then write the two variable to flash.However,this method would be inconvenient when there are many data to write to flash.So could you give me some advice?Thanks

RE: Cann't write data to flash by using pstorage.

Dan Danknick — Wed, 21 Oct 2015 14:25:11 GMT

I had this same problem the first time I used PStorage. I suggest you add the following function:

// 
// This function is called from the System event interrupt handler after a system event has been received.
//
static void sys_evt_dispatch(uint32_t sys_evt)
{
    pstorage_sys_event_handler(sys_evt);		// Run the state machine on the PStorage module
}

And then register it at the end of your ble_stack_init() function with:

// Register with the SoftDevice handler module for sys events.
err_code = softdevice_sys_evt_handler_set(sys_evt_dispatch);
APP_ERROR_CHECK(err_code);

Good luck! -- Dan