Deckel FP5 Gearbox Comp

Thanks for the information. I will eventually be getting into my console to look at the selector switch wiring. I will replace them with 5 bit encoders if necessary.

https://www.indiastudychannel.com/attachments/Resources/137809-15246-1.bmp
That's roughly the schematic of mine . Absolutely easy and simple to build even on a proto board.

 Attached is a copy of a console diagram. Looks like I already have 5 bit encoder switches. The pinout to the chips shows ABCDEFG like a typical 24 position encoded switch. Just need to figure out what encoding its using.

 

 

That should do it . Even if it's gray coded you can still get it going . There's a debug pin that outputs the decoded speed . What I usually do is write down a table with what it decoded and where the switch points at . After that it can be modified in the component itself .
Only thing I'm not sure are those logic elements . There's probably some control signals going there . Might need some reverse engineering .

I am going to ditch all the circuitry in the console and wire directly into the switches, keypads and buttons. Going to require a lot of Mesa inputs....

Will have the main LCNC PC (6i25 7i77 7i84)  in the hardware cabinet for all the existing IO and will probably go SSerial interface to separate cards in the control console. Was thinking 7i73 keyboard controller but probably need more inputs so:  7i69 better?
 

I can send you the KiCAD project for the PCB . It's super simple to build . Can be mounted on a proto board as well .