Soldering a PS2 cable

[Mokka]

I have scavenged an old Cherry G80-3000 (I am pretty sure it was made before 1989, it says "Made in West Germany" on the back), the only problem with it is, the PS/2(?) cable has been cut off from the keyboard!
Pictures:
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(sorry for the bad quality, don't have a proper camera at hand right now)

Is it possible to take a working PS/2 cable out of another keyboard and solder it on this?
If yes, could someone post some schematics for the soldering?

[mich]

Yes, it's possible. To find out which wire is which, look for the following pattern on the PCB:

Code: [Select]

                           _____
vcc -----+-----+-----+------|    |
         |     |    _|_+    |    |
        | |   | |   ___     |    |
         |     |     |      |    |
data ----+-----|-----|------|    |
               |     |      |    |
               |     |      | uC |
               |     |      |    |
clock ---------+-----|------|    |
                     |      |    |
                     |      |    |
                     |      |    |
ground --------------+------|____|          



ground --------------------- metal parts in the keyboard
The resistors will be in 2k - 4k range. If they happen to be absent, you will recognize the clock and data lines as the only ones connected only to the microcontroller. There is no way to tell these lines apart, but reversing them shouldn't cause any permanent damage.

You might also want to search the forum for posts about disassembly and/or repair of the G80, maybe somebody has already figured this out.


Once you identify the wires coming from your keyboard, match them with respective wires in the PS/2 cable (google "PS/2 pinout") and test it in some motherboard you don't care about too much

[Mokka]

Thanks for your help, I've already figured it out on my own after spending a few hours measuring stuff with a multimeter.

Keyboard works perfectly, apart from the occasional double characters when I press L, M or H. Is it a known problem?

[Mokka]

Anyone?

[mich]

Dirty switches?

IIRC there were several threads here about cleaning them.