[sdiy] J-Wire Woes

[doof]

Hello Again,

Thanks for all your helpful suggestions thus far.  I realize my first post was a bit vague, so I decided to test more thoroughly and provide a schematic.  

I've found the Pro-One schematics online; they can be viewed at: http://www.hylander.us/images/schematics/sequential/pro1-schematics.pdf

If you're on this list -- many thanks for posting this on the web.

The column I'm having trouble with is D#0, B0, G1, D#2, B2.

The continuity of the ribbon checks out fine.  (luckily its the computer-type removable kind)
On the keyboard pcb I've tested for continuity from the slot for pin8 to each of the diodes of the problem keys.
On the main board I've checked the continuity from ribbon slot 8 to the leg of P13 of the U113 microcomputer IC socket.

>From this I believe I can conclude that the leads are intact going from the keyboard pcb to the IC socket.
Perhaps the next thing to check would be whether the IC is properly seated in its socket (it looks like it is).
Would the next logical step be to replace the IC?  I've had a quick look at mouser.com was unable to find an IC designated U113 or 8021.  Any suggestions for a replacement?

Thanks.

-Tom
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