Service Manual wanted for DEC VT-125 terminal

From: Paul Williams <celigne_at_celigne.freeserve.co.uk>
Date: Sun Mar 30 02:00:00 2003

Dan Veeneman wrote:
>
> "VT125 IC Error"
>
> Does anyone have a service manual or other troubleshooting
> documents that might help me fix this error?

I don't think I have the service manual, but here are the six types of
errors indicated by the self-test error messages, from the User Guide.

VT125 Offline VT100 text terminal is LOCAL. LOCAL was saved
                in SET-UP, or user permanent memory problem.
                Terminal can only process received graphics
                commands.

VT125 BM Error Video bit map memory has one or more bad pixels.

VT125 VG Error Vector generator could not draw sample shape.
                Graphics probably does not work, but terminal may
                communicate normally.

VT125 IC Error Internal communications failed. VT125 cannot
                communicate with VT100. Terminal can only
                process received graphics.

VT125 SC Error Auxiliary port failed data loopback test. Terminal
                cannot send data to printer.

VT125 EC Error Computer port failed data loopback test. Terminal
                can only operate as text terminal in LOCAL.

As this is a comms failure, I would check out the 24-pin and 16-pin
cables that run from the graphics processor to the other boards. I think
there are tight twists in both cables that may have cracked over time.

- Paul
Received on Sun Mar 30 2003 - 02:00:00 BST