DFU update bootloader from SDK12.3 to SDK14.2

[Krystian]

Hello,

when I try to update bootloader on nRF52 from SDK12.3 to SDK14.2 using DFU over BLE I get  INSUFFICIENT_RESOURCES error. I think it is caused by different sizes of bootloaders.

Is there any way to safely update bootloader over BLE?

[Hung Bui]

Hi Krystian, 

 

I don't think there is much change in the bootloader size in SDK v12.3 vs SDK v14.2. 

What was the start address of your bootloader in SDK v12.3 ? As far as I can see they both start at address 0x78000. 

 

Could you provide the log when you see the error ? 

[Krystian]

Bootloader in SDK12.3 starts from 0x75000 and in SDK14.2 from 0x73000.

Logs bootloader:

 0> :INFO:PB: Init data len: 60
 0> :INFO:Handling signed command
 0> :INFO:Prevalidate FAILED!
 0> :INFO:Sending Response: [0x4, 0xa]

Logs form nRF Connect:

When writing 'EXECUTE' command to Control Point Characteristic of DFU Target: Operation code 4 (EXECUTE) failed on DFU Target. Result code 10 (OPERATION_FAILED)

[Hung Bui]

Maybe you were using the _debug version of the bootloader in SDK v14.2 

The non debug should start at address 0x78000. 

[Krystian]

Both bootloaders are the _debug version.

[Hung Bui]

It should be 0x73000 if you are using debug version in SDK v12.3. If it's not, please change the configuration. 

 

[Krystian]

The problem is that I have bootloader SDK v12.3 on several devices and I can't change it without DFU.

Probably i will try with bootloader in SDK v14.2 non debug version.

[Hung Bui]

Yes, you can try that. Be aware that with non debug mode, you need to make sure the new bootloader version is > the current one. 

There is a possibility to erase the UICR and write a new UICR to increase the size of the bootloader before swapping the bootloader however it's complex and have a risk to brick the device if the DFU process is interrupted.