nRF54H20 : understanding difference in uicr_merged.hex

Hello,

I am using ncs 2.7.0.

I am programming ncs/zephyr/samples/basic/blinky on nRF54H20 using below commands and it works.

nrfutil toolchain-manager launch west build ./ncs/zephyr/samples/basic/blinky -- --pristine -b nrf54h20dk/nrf54h20/cpuapp
nrfutil toolchain-manager launch west flash

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[158/158] Linking C executable zephyr/zephyr.elf
Memory region Used Size Region Size %age Used
FLASH: 35412 B 296 KB 11.68%
RAM: 9544 B 256 KB 3.64%
DMA_RAM21: 0 GB 16 KB 0.00%
DMA_RAM3x_APP: 40 B 4 KB 0.98%
IDT_LIST: 0 GB 32 KB 0.00%

uicr_merged.hex is 112.8 kB.

Flashing programs 3 images to the dev kit. 

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Then I copy blinky folder to another path outside of ncs folder.

I give the same build commands pointing to that new location.

the uicr_merged.hex file is however smaller in size, it is now 103.6 kB.

Memory used is same as above.

But the west flash command only programs 1 image now.

And the LED does not blink.

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How do I know what 3 images are being programmed with the 1st step?

How can I manually program those hex files? Are there any nrfjprog commands to do the same?

What could be the difference in building from 2 different locations and why are the ucir_merged.hex files different?

Thanks,

Dhara

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