pstorage: unable to write twice on the same block

[ben38]

It seems that is not possible to rewrite data on a block ? I want to persist some data. The first time (after erasing all the flash memory) I store a data on a block, it works: I restart the chip, and I can retrieve my data. But the second time, the data is not replaced. Is it a normal behaviour ?

If I call pstorage_clear before writing the data on the second time, it works... But pstorage_clear clears all blocks, not just the one I want to clear...

As a workaround, I register a block (pstorage_register) for each data I need to save. Is it correct ?

[Krishna Shingala]

Hi Benoit,

The pstorage_clear API clears all blocks registered by the application, not only one block. This is currently an implementation limitation, the API itself take a 'size' parameter to allow for selective clearing of data. Reason for this limitation is that clearing of flash is permitted only per page and not individual words.

Coming to your first issue of write not succeeding the second time, it is strange and unexpected. Is it possible to provide sequence of operations you are performing. Also, are you certain that you have received success events for each of the pstorage_clear and pstorage_write that you have requested?

Regards, Krishna

[ben38]

pstorage_clear works: If I execute the pstorage_clear and in the callback I execute pstorage_store, it works correctly. But if I execute pstorage_store directly (as in the attached source file), the data is not stored. The callback is called correctly without error (as I can see using gdb).

main.c

[Krishna Shingala]

Hi Benoit.

Have you tried to evaluate the results making scope of 'data' global?

Please note that the pstorage_store requires memory to be resident. Hope this helps!

Regards, Krishna

[ben38]

No, it doesn't help.

I quickly check the examples (bootloader, bondmngr ? ), and it seems that pstorage_clear is always called before pstorage_store...

[Ken Matsui]

I'm also in same situation. And, I was able to resolve by calling pstorage_clear before pstorage_store.