Bangle.js App Loader returns "Upload failed, Unexpected response"

As for SWD, if you have Raspberry Pico then you can make it very easily into SWD debugger by just uploading picoprobe uf2 file and then connect 3 wires (gnd,swdclk,swdio) and use openocd on Windows or Linux. Also bigger Pi works alone with its GPIO but may need a bit more tweaking to get working.

Hi - sorry to hear it's not working. Why did you run the code in https://www.espruino.com/Puck.js#recovery-after-2v04-installation - had you actually installed an earlier firmware version that had effectively bricked it beforehand?

It's an odd one - I had tested that code previously, but I bet on the device I used no code was saved in storage, so address 0x78000 was empty and the softdevice continued as normal.

So as @fanoush says I think you'll have to connect up SWD and rewrite the firmware.

Do you have any of these devices handy?

• nRF52DK (easiest!)
  
• Raspberry Pi Pico
  
• Raspberry Pi (less easy, but possible)
  
• STLink clone
  
• DAPLink (costs around £10) - and pretty straightforward
  

@fanoush @Gordon sorry guys, I ordered nRF52DK and didn't have time to get to this since then.
Had this tab open for this whole time and was just clearing my open tabs when I noticed your replies. Thanks for getting back to me.
So, while I was waiting for the nRF52DK to arrive I managed to turn an ESP32 dev board into an SWD debugger and also managed to copy the firmware from my Puck 1, I tried to write the dump to Puck 2 but looks like that made everything even worse. No lights are comming up at all when I connect it to the battery.

So, I have my nRF52DK on my desk now and would like to have some guide on how to recover the dead Puck 2.

Thanks in advance!

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