Don't understand page numbering for sd_flash_write and sd_flash_erase

RE: Don't understand page numbering for sd_flash_write and sd_flash_erase

huyuxiang — Tue, 25 Apr 2017 07:37:00 GMT

USing sd_flash_page_erase() function , first ,you should call ble_stack_init() function.

RE: Don't understand page numbering for sd_flash_write and sd_flash_erase

huyuxiang — Tue, 25 Apr 2017 07:34:20 GMT

Using sd_flash_page_erase() should after the ble_stack_init();

RE: Don't understand page numbering for sd_flash_write and sd_flash_erase

SoothingMist — Thu, 02 Jun 2016 16:27:17 GMT

main.c

Am just getting my first real exposure to embedded programming but the attached from an IAR/Nordic example (flashwrite_example) appears to contain an implementation of the necessary approach.

RE: Don't understand page numbering for sd_flash_write and sd_flash_erase

David Smoot — Mon, 10 Mar 2014 21:29:07 GMT

Ok, I don't know if this will help anyone else but here goes in case:

My original code did not work for two reasons:

If you use the sd_flash_* API only allows one pending operation at a time. Learned this from a reply on another thread flash_write.
But more importantly is the scope of the variable being written. If you use a local function variable as an argument to sd_flash_write, it will most likely be out of scope and not holding the data you want when the soft device gets around to actually performing the flash write.

RE: Don't understand page numbering for sd_flash_write and sd_flash_erase

David Smoot — Mon, 10 Mar 2014 16:50:30 GMT

Some progress due to a very smart coworker. A reason the code above does not work as I posted it is that I am trying to schedule a write operation immediately after scheduling the erase operation. The erase operation has not completed yet when I call sd_flash_write. I am still working on my code, will try to update this thread if / when I get it correct.

RE: Don't understand page numbering for sd_flash_write and sd_flash_erase

Håkon Alseth — Mon, 10 Mar 2014 14:52:08 GMT

Hi David,

That should be valid, unless there's something else in your application using that address area.

Best regards Håkon

RE: Don't understand page numbering for sd_flash_write and sd_flash_erase

David Smoot — Mon, 10 Mar 2014 14:48:33 GMT

Thanks, I will try the call back method and the pstorage API if the call back does not work.

Can you confirm that my addressing is correct? If I use the sd_flash_write function to write to page number NRF_FICR->CODESIZE -1, can I then access the first address on that page by dereferencing (NRF_FICR->CODEPAGESIZE * (NRF_FICR->CODESIZE - 1))?

Thanks, David

RE: Don't understand page numbering for sd_flash_write and sd_flash_erase

Håkon Alseth — Mon, 10 Mar 2014 11:46:23 GMT

Hi David,

The softdevice will schedule the write-process in between connection intervals and give you an event back when the write has finished (NRF_EVT_FLASH_OPERATION_SUCCESS or NRF_EVT_FLASH_OPERATION_ERROR) in the callback set in function "softdevice_sys_evt_handler_set(my_handler);".

Note: if you're using pstorage module, it uses the last two pages by-default, and you should then use calls to pstorage instead of directly accessing the sd_*-API.

Best regards Håkon