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?

[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.