Doozer wrote: ↑Tue Apr 05, 2022 7:24 pm
The tool from
https://github.com/floppes/RTD266xFlash is producing good dumps with a RPI. The details about how to set it up is available in the readme.
Nevertheless, you will be able to flash a new binary without enabling the write operations. I think you already know this by reading you.
Unfortunately, it seems like nothing I do brings the display to life with any firmware but your 2550 dump - using a Raspberry Pi seemed slightly more successful, but the result is the same. It's completely non-functional with anything else. The closest I got was modifying the EDID in the 2550 dump and successfully flashing
that, but that caused more problems than it solved - it proved the data is getting on there successfully, at least, and that it's possible to modify it.
The only real clues I have are a) that invariably, any flash but the 2550 dump results in a blank EDID according to i2c dumps, and b) that sometimes the firmware I flash reads out slightly differently to how I initially flashed it. But the last time was only by a few bytes.
What could be the difference between our boards, that flashing yours with alternate firmwares works and mine doesn't? What is the USB tool doing to make the code work that the available software methods are not? Is there some way to force it to work using i2c commands?
I might suggest you try using the RTD26xxPy tool to flash firmwares yourself, and see what happens and what the difference is. I'm not
really in a position to spend $40 on a programmer tool that only
might work, but I'm getting awfully tempted to.