Bootloader code target size overwrites Pstorage allocation

[rama]

SDK 9.0.0 sd s110

I want bootloader to store some persistent data at the APP DATA location. while going through the bootloader(dual_bank_ble_s110) source code, i noticed that it is registering two pages starting at 0x3F800 for persistent storage module.

but the bootloader(dual_bank_ble_s110) project target settings shows that it is reserving size 0x3C00(15K) starting at location 0x3C000 for the bootloader code.

In such case there is only 1K space left for persistent storage above the bootloader code, How is it possible that the code manages 2k persistent storage without overwriting code.

/*********************Question Update after first answer************************************/

when i try to include my source code to bootloader(dual_bank_ble_s110) project. It gives the following error. I don't have any clue what going on, i also tried to increase the BOOTLOADER_REGION_START by 8 pages(0x0003A0C0). it shows the same error. Can you please help me with this.

[Vidar Berg]

Hi, there are two separate pstorage instances in the bootlaoder, one for the bootloader settings page @ 0x3FC00 and the other one for the banked region(s). Note that the bootlaoder uses Pstorage RAW.

[Vidar Berg]

You will likely have to allocate more flash if you are adding code to the example as it tight already. But note that in addition to adjusting the start address you will also need to change the UICR.BOOTLOADERADDR to reflect this new start address. E.g., dfu_types.h -> #define BOOTLOADER_REGION_START 0x3A0C0 (start should ideally be page aligned).

The error you saw should disappear if you subtract the size of the bootlaoder settings page from the allocated flash size:

0x40000 - 0x3A0C0 - 0x400 = 0x5B40 so IROM1 start: 0x3A0C0 size: 0x5B40.