Amiga keyboard membrane/board mapping

[solarmon]

Hi,

In trying to troubleshoot why some keys on my A500 keyboard was not working, I came across this excellent EAB thread:

http://eab.abime.net/showthread.php?t=81893

The information here was invaluable in helping me understand the key mappings, but what I really wanted was the equivalent of the board views at the excellent and invaluable amigapcb.org site. Sadly, this does not have any keyboard board views.

The alternative solution I came up with for now is to use yEd Editor (https://www.yworks.com/products/yed) to create the mappings and allows you to select and highlight nodes and traces to aide in troubleshooting the keyboard membranes.

The membranes are scanned in and I use the image to mapped out the traces by hand in yEd.

The GraphML files generated by yEd for these mappings can be found at:

https://github.com/solarmon/Amiga-Keyboard

So far I have mapped out the following keyboards, but I'm looking to add to that list:

A500 / Mitsumi A619A (Large ENTER key)
A500 / Mitsumi A619B (Small ENTER key, Left/Right Euro keys)
A500 / Samsung 312502-12 (Dual membrane)
A1200 / QWERTY A1200-A 56C774A (Reproduction)
A600 / 8770-0056 REV E (Blue)

Here is an example of the mapping of the Mitsumi A619A membrane exported as an image.



I have used some different colours for the traces to try to distinguish between the different types of traces.

It is best to view the mapping in the yEd Editor as this allows to you highlight and search traces.

I hope these mappings will be useful to others in troubleshooting and repairing their keyboards.

[solarmon]

Amiga A600 Blue membrane (8770-0056 REV E) now added.

[aeberbach]

Keyboard schematics available in Kicad format:
A1200: https://github.com/aeberbach/A1200KB
A600: https://github.com/aeberbach/A600KB
These have been used to make working keyboard PCBs using MX keyswitches.

[solarmon]

Originally Posted by aeberbach

Keyboard schematics available in Kicad format:
A1200: https://github.com/aeberbach/A1200KB
A600: https://github.com/aeberbach/A600KB
These have been used to make working keyboard PCBs using MX keyswitches.

Ooh, thanks! I will take a look!

Is that schematics of the actual original membranes, or of a new board?

[aeberbach]

No it's a new board, my routing. If you want an A1200 one I have four left I think? There's a thread about them.

[solarmon]

Originally Posted by aeberbach

No it's a new board, my routing. If you want an A1200 one I have four left I think? There's a thread about them.

Ah, OK. If it is for a new board and there are already kicad schematics of them then I don't think I need to map it.