Dolch Pac 64 PS/2

[codyeatworld]

So I have a dolch pac 64 pcb board. and I desoldered a few of the switches for another board.

But I got my mimic ps/2 cable today and I soldered it on and it dosen't seem to work when I plug it in. (just to test it out real quick while I'm waiting for more switches)

Is there anything I should be aware of?
Do I need a switch in all pcb holes?

Thanks

- Cody

[Michael]

I did a few of these mods, here are the legends for the cables. You just need to know which are which on mimic's cable

[codyeatworld]

Thanks for the pic, how would I find out which are which?

They were the same colors and i just soldered the same color in the same hole.

[Michael]

Thanks for the pic, how would I find out which are which?

They were the same colors and i just soldered the same color in the same hole.

The colors there were for a cable I got from a different vendor. But what you are looking at is the back of the add-on PCB inside the Dolch. So the smaller daughterboard attached the the main PCB, that is the back of that.

[codyeatworld]

Yes that is where I soldered the wire into.

The colors matched so they should be the same right? Mimic knew so my cable was ready to go I thought.

[Maverick-1978]

Hi there! Sorry to necropost, but looking for some help.

Have a Dolch keyboard that I bought w/o keycaps here from a forum member sometime back. Not sure if it came from a PAC-62 or PAC-64. It has the G80-1813HFU board inside.

I finally got a MY-1800 case to swap boards into, and while I was at it, I wanted to do a permanent PS/2 mod.

I used the Dolch diagram as shown above. Wiring to PS/2, I followed the PS/2 diagram here, so

Dolch GND -> PS/2 Pin 3
Dolch +5V -> PS/2 Pin 4
Dolch Data -> PS/2 Pin 1
Dolch Clock -> PS/2 Pin 5

Wired it all up, checked for continuity (passed) and shorts (none), then connected! .... and got nothing. No data output, no LED response, yet voltages checked out at the pin.

Hmm... Found a cold solder joint on one of the 3 LEDs, fixed. No go. Thought I may've reversed my pinout on the Dolch board (mixing up male/female views), so I reversed them. Still no output.

At this point, I got to studying my My-1800 driver board. The boards used the same main chip, and while the PCB layouts were slightly differnt, both appeared to use the same two connections from the keyboard to the driver board: one 19-pin connection, one 8-pin connection, except that the MY-1800 had membrane housings there instead of direct-soldered like the Dolch part. So I figured I would swap them around and try again.

I desoldered the membrane housings from the MY-1800 board, cleaned up with alcohol, then desoldered the wire ribbon cable on the Dolch board that connected keyboard and driver board.

That done, I soldered the Dolch Keyboard to the MY-1800 driver board, verified continuity between points and that there were no shorts. Plugged into a computer, and still no go...

FWIW, toning out the MY-1800 connector, I was able to verify the PS/2 diagram I linked above, so at least I know the PS/2 side is ok.

So... I guess my questions are these:

(1) Are my pinouts correct, as described above?
(2) Is my Dolch G80-1813HFU just dead? (note that my soldering is quite good and I've not damaged either boards in any way/shape/form)
(3) Can these driver boards even be switched between keyboards as I've described above?
(4) If I did have something reversed, could it have just fried my keyboard drivers PCBs? -  the computer side PS/2 connections still work with my other keyboards

Any help would be greatly appreciated. I'd really like to get the vintage cherry blue board up and running.

Thanks so much!

[codyeatworld]

No worries, I actually never got mine working yet either, you have done a lot more testing than I have or am capable of at the moment. I have been really busy.

I'm pretty sure my ps/2 cable is soldered correctly, but I get no response from my board when plugged in.

I know quite a few people have done this mod successfully and hopefully theyll see this and help us out.

 - Cody

[kishy]

This attached image was previously present on the site in other related threads before an exploit rendered most functions of the site nonfunctional, ages ago now. Hopefully it's of use to you.



Note that the 4P4C connector as seen on a PAC 64 should (should!) be the same as the inside 4 pins of this one. Someone way back when confirmed that for me, but it may not be consistent on all units...

[codyeatworld]

Glad you saved the pic then. 
I will attempt this again when I have some more free time.

This attached image was previously present on the site in other related threads before an exploit rendered most functions of the site nonfunctional, ages ago now. Hopefully it's of use to you.

(Attachment Link)

Note that the 4P4C connector as seen on a PAC 64 should (should!) be the same as the inside 4 pins of this one. Someone way back when confirmed that for me, but it may not be consistent on all units...

[Maverick-1978]

Kishy, was hoping that you'd respond - greets from VCF

According to the original seller, my board was from a PAC 64, and it used a 4P phone connection.

Surprisingly enough, this connection is different from the PAC-62 that I later purchased (both for the board/caps and also for the computer - a 200mhz portable gaming machine? Yes, please)

Anyway... wire orientation seems to match your interior diagram as well as the ones the OP posted above.

Any ideas on how I would further troubleshoot this issue?

[IvanIvanovich]

I used other G80-1800 as my guide when I soldered in my cable, sourced from a G81 which had the same cable and wire colors. It worked correct my first attempt.

[codyeatworld]

Lucky you!

I think I'll give this another go.

Will it still work if I removed a few switches completely? or do all of the diodes and switches need to be soldered in?

[IvanIvanovich]

Missing switches won't matter, only can't use that one obviously.