sd_flash_write hangs after 10 words written

RE: sd_flash_write hangs after 10 words written

Elena — Mon, 29 Sep 2014 06:46:36 GMT

Hi again

I've discovered the problem. My fault: I wasn't calling the scheduler from my loop. I've edited the code as follows:

	for(i=10; i<256;i++){
		buf[0] = i;
		res = sd_flash_write(FLASH_DIR_LAST_PAGE+(i*4), (uint32_t *)buf, 1);
		TIMER_BASE_Delay(1000);
		**app_sched_execute();**
	}

Thanks for your help

Cheers

RE: sd_flash_write hangs after 10 words written

John — Thu, 25 Sep 2014 17:21:16 GMT

I don't know why the delay is not working for you. However, I don't have your code so it is hard to tell. Does the call the sd_flash_write ever return anything other than NRF_SUCCESS?

RE: sd_flash_write hangs after 10 words written

Elena — Thu, 25 Sep 2014 16:53:56 GMT

Thanks for your reply. You're right: I'm waiting for one second in order to wait sufficient time to perform de operation. One second should be more than sufficient, so I don't understand what's happening.

I'll review my code and check the pstorage module.

Thanks again,

Regards,

Elena

RE: sd_flash_write hangs after 10 words written

John — Thu, 25 Sep 2014 15:35:22 GMT

The call to sd_flash_write returns before the write operation is complete. I'm guessing you know that since you have the delay in between calls to sd_flash_write. However, you really should be waiting for a flash system event before proceeding onto the next write operation.

This is where pstorage is helpful as it will queue up to, I believe, 20 flash operations. So, you can fire off a number of flash operations and pstorage will take care of them. The flash events will come to you system event handler and you can then call the pstorage event handler and it will dequeue the next operation and run it. NOTE: You will want to check to make sure that the system event is a flash event before calling the pstorage event handler as it doesn't screen the event type (at least it doesn't in revision 5.2.0 of the SDK).