Advertisement Data stored in Flash Memory

[shaileshbc]

I have nrf52840 dongle and sdk nRF5_SDK_17.0.0_9d13099.

I would like to know, is there is an example in which, Advertisement Data is stored in flash memory and reading and writing can be done on it.

In order to protect data from getting erase after dongle turns off and on.

I saw the example of storing data in flash memory, but would like to know, how do I point the advertisement data to flash memory.

regards

Shailesh

[Jared]

Hi,

No there isn't an example on this in SDK but you could achieve this by combining BLE with the FDS library. You would have to open the record that contains the stored advertising data and then initialize the advertising_init struct with this data.

regards

Jsared

[shaileshbc]

Hi Jsared,

As per your suggestion, I used the FDS library and stored advertising data.

but now I am finding an issue is that each time when I write the data, the size of a memory where data is written is increasing.

After writing data, record_Id of fds_record_desc_t, gets incremented.

but gc_run_count remains zero only.

do I have to remove all records, as I just want a single record only?

regards

shailesh

[Jared]

Hi,

Are you updating already existing records or are you writing new ones every time? What function are you calling when you write the data?

regards

Jared 

[shaileshbc]

Hi Jared ,

I want to modify an existing record.

I will explain the flow of the code when I want to write the exiting record

first, I use fds_record_find to get the record then I use fds_record_update function.

if I use fds_record_write instead of fds_record_update, then the record in flash memory doesn't change.

so I tried to delete the record, by calling fds_record_delete function and then fds_record_write.

Even after that, all the records are shown in flash memory.

regards

Shailesh

[Jared]

Hi,

fds_record_update() will update the descriptor to a new record and invalidate the old one. The old will then be deleted when you run the gc. fds_record_write() however will make a new record, and the old record will not be deleted, resulting in more usage of space. The method of fds_record_update() would be the correct method if you want to update a record.

regards

Jared