Model F Controller replacement

65caliente · 09 Feb 2023, 18:13

Hello, I have a couple Model F XT's that may need the controllers replaced. I am in the process of replacing the foam in them but before I did anything one of them would register random typing continually and the other wouldn't work at all. If the controllers do need to be replaced I am guessing that I wouldn't be able to just replace the IC as it would need programmed and I don't have the equipment of knowledge to do that. I was looking at a post where the guy dremeled off the controller portion of the circuit board and soldered in a xwhatsit controller to the test points.

However the xwhatsit has been redesigned so I am not sure where to solder the wires anymore as I was going to use the above picture as a reference.

Anybody know the correct locations for soldering with this new design?

Muirium · 09 Feb 2023, 18:41

You can assign the pins yourself to rows and columns. The modern controllers are all programmable.

65caliente · 09 Feb 2023, 19:16

Muirium wrote: 09 Feb 2023, 18:41 You can assign the pins yourself to rows and columns. The modern controllers are all programmable.

So I just solder the wires into any test point I want and program it later? Seems strange but I have no idea about these things. I know there are traces from the front and back of the sensing circuit. What is the program I need to use to do that?

Muirium · 10 Feb 2023, 09:35

This will explain it better than I can. Thoroughly worth the read:

https://static.wongcornall.com/ibm-caps ... odel_f.pdf

That’s Xwhatsit’s excellent documentation for his firmware which is what all these controllers were originally built for. Other (in certain areas better) firmwares are available now, but for ease of learning his may be the best place to start.

65caliente · 10 Feb 2023, 21:29

Muirium wrote: 10 Feb 2023, 09:35 This will explain it better than I can. Thoroughly worth the read:

https://static.wongcornall.com/ibm-caps ... odel_f.pdf

That’s Xwhatsit’s excellent documentation for his firmware which is what all these controllers were originally built for. Other (in certain areas better) firmwares are available now, but for ease of learning his may be the best place to start.

That is awesome, thank you!