Openplotter in an Oldplotter!

[Vamonos]

I would love to get the joystick working , but It seems like It outputs are: up-left, up-right, down-right down-left. Those direction has a corresponding pin wich is earthed when pushed. When you push it straight up , you get about 200 ohms to earth on both up-left and up-right. other directions works the same.

Regarding the joystick.  Perhaps I'm not thinking correctly, but it seems that one quad nor gate on a piece of perf-board could solve your problem.  With the up-left tied to one input and the up-right tied to the other, you would get a high out of the nor gate that signifies up.  Likewise, you would wire up the other three combinations and end up with up, down, left and right outputs.  Something like a 74LS02 (if you hare running 5 volts should do the trick).  Richard