Getting weird behavior from the board while adding the application version

[Pavan kumar]

Hi all,

I'm trying to add application version in the signed bootloader to prevent the downgrade of application. So I'm directly writing the application version to the flash like

attribute ((section(".appVerStartAddress"))) volatile uint32_t m_application_version = APP_VERSION;

I would like to put the application version at last four bytes of the application area. The application will start at the address 0x18000 and I come to notice the DFU_BANK_0_REGION_START = 0x18000 and DFU_BANK_1_REGION_START = 0x28E00 that means I can put .appVerStartAddress = 0x28DFC, ( 0x28E00 - 0x04 = 0x28DFC ), But when I'm trying to do that I'm getting weird result ie, the first 0x200 byes of data is not written to the flash after doing DFU, ie 0x18000 to 0x18200 is empty when I read the memory. This will happens when I try to put the app version in between the locations 0x28C00 to 0x2E00, If I use the location < 0x28C00 its working fine. And after analyzing It come to know that DFU_BANK_1_REGION_START is not getting flashed upto 0x200 bytes ie from 0x28E00 to 0x29000 is empty ie, all are 0xff. So it reflecting in DFU_BANK_0_REGION_START

Getting confused why can't we write the locations between 0x28C00 to 0x2E00.

I would like some one to help me in this regards

and I'm checking the appVerStartAddress in the bootloader

I'm using the nrf51DK board SDK9.0 using the signed_bootloader example. and I'm attaching the linker script that I'm using here ble_app_template_gcc_nrf51.ld

[Vidar Berg]

Hi,

It sounds like the changes in your scatter/linker file has caused the start address to be move upwards in flash. Are you using GCC or Keil? Can you share the changes you made to the linker script so I can try it here?

Update 22/2 - Verified linker settings

Ok, so the linker settings were correct. I can't think of any obvious reasons as to why only the first 200 bytes are "lost" considering that the start address is hardcoded within the softdevice. Is it possible that the the device is being reset shortly after the call to dfu_activate_app()->pstorage_clear() in dfu_dual_bank.c?

[Pavan kumar]

Thanks for you response Vidar I'm using gcc and I attached the linker script.

[Pavan kumar]

If I reset just after pstorage_clear() no data written to the flash