How to flash bootloader to thingy 52?

[Gova]

I am a newbie for Nordic development boards. I recently bought a thingy 52. When I was searching for how to upload a custom firmware of my own (After disabling few BLE services), I came across this link. OTA-DFU - Generating your own packages

I have installed nrfutil and have generated Private key. But how am I supposed to flash the bootloader? I have only one thingy board in hand.

Once I have my ZIP file, I can do a OTA-DFU with my phone. But please let me know how to flash the bootloader onto the board over the air.

I would be glad if someone can help me. Thanks a ton in advance.

[Gova]

Thank you so much for your reply. Yes with the attached images, I think i need a nRF DK to program the bootloader.

[ToasTer86]

Hey Bjorn, thanks again. That is just the nrf52832_xxaa_s132.hex file generated by Keil?

EDIT: I used nrfutil to create a *.zip file from the *.hex file from the secure_boot project. Using nRFconnect on my phone I can see the thingy in DFU mode. I tried uploading the *.BIN , *.DAT , *.ZIP file using the dfu button at the top. It starts connecting and than it just disconnects.

When using nRF connect on my desktop through a DK52 PDK I get the error below:

DFU failed with error: When writing 'EXECUTE' command to Control Point Characteristic of DFU Target: Operation code 4 (EXECUTE) failed on DFU Target. Result code 11 (EXTENDED_ERROR) Extended error code 5 (FW_VERSION_FAILURE).
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