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.

[Bjørn Kvaale]

Edit: I think that should be fine to make a zip file from the hex file. You have two options regarding doing an OTA-DFU, but only one option if you want to upload custom FW to the Thingy. Since you have an nrf52840, you can attach a JTAG cable to the P19 debug out port on the top left of the PDK. Then, attach the other end of the JTAG cable to the Thingy JTAG connector located under the cover to the right of the usb connector. Essentially just follow this guide here. That is the method I normally use for OTA-DFU & Secure DFU of the Thingy.