[Coco] Trying to get a KoKo2 working

Arthur Flexser flexser at fiu.edu
Sun Aug 25 15:27:27 EDT 2013


I think it's more likely that there are broken traces on the ribbon
cable.  Have you tested the continuity between the two ends on each
trace?

 A stuck joystick button can also prevent the keyboard from working.

Art

On Sun, Aug 25, 2013 at 3:06 PM, Chris Osborn <fozztexx at fozztexx.com> wrote:
> Thanks to Retro Canada I got a copy of the schematic and was able to test the PIA and the keyboard connector on the PCB and it's working fine. Pulled out a wire and jumpered the pins on the connector and I was able to "type". So it looks like the problem is entirely the plastic membrane inside of the keyboard. Is it possible it has become oxidized and if so, can it be cleaned? It has a black coating on all the traces and I had to scratch through it a little bit for the DMM probe to get a signal. I'm afraid of scraping it off though and having no trace left.
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco



More information about the Coco mailing list