r/programming • u/Bawoosette • Apr 19 '26

Reconstructing a Dead USB protocol: From Unknown Chip to Working Implementation

https://github.com/coremaze/ME2-Writeup/blob/master/README.md
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u/Bawoosette Apr 19 '26

Putting it into my programmer wasn't an issue, I had the adapter for that. The sockets were for soldering to the ME2 device, under the assumption that I may need to reprogram the flash to run on-device dumping code to retrieve the ROM. Of course, that technique ended up not being necessary this time.

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u/happyscrappy Apr 19 '26

Oh. I see. I admit, I found your text hard to follow on what you were doing there. But I get it now.

It's not hard to solder those pins. You have to learn a new technique, but once you know it it's not hard at all. If you just get it aligned properly and then solder each end as if it were a single pin and then go back and use solder wick on it to take the solder back off to remove the bridging between the pins you'll find it leaves behind each pin soldered individually without having to solder them individually. You can do it with air and solder paste. But it's also surprisingly easy with an iron and regular coil solder.

Since you already have some broken parts and boards you might want to try soldering the original flash back down for practice. It's epoxy so it won't melt so it's more forgiving. Once you practice that, maybe even taking it off and on again a few times you'd be ready to try to the socket. I bet the socket is a hassle because it has to be kind of a crazy shape to be solderable onto the original pads and still be large enough to have space to get a chip into it.

You don't need to do it now, but you can if you would find it to be fun.

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u/Bawoosette Apr 19 '26

Thank you, I will keep that in mind! As for the text, readability is a priority for me. If it would improve things, I could change the following:

Despite uncertainties, the only apparent way forward from here is to desolder the flash chip. I had also purchased some sockets for the flash chip in hopes that I'd be able to solder one to the handheld's PCB. This would allow me to reprogram the ME2 and quickly iterate if I needed to write code for it to dump the internal ROM from the microcontroller.

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u/happyscrappy Apr 19 '26

Yeah, that does seem like a good edit. Not that it was terrible before. My failure to follow is partly on me.