11/34 sanity check

Jörg Hoppe j_hoppe at t-online.de
Sun Apr 26 09:44:04 CDT 2015


my post on classiccmp is not appearing on the list, so here a direct mail:

> So at this point all voltages are spot-on, the AC LO and DC LO signals
> are high (these are active low, right?) but I can't get the machine to
> respond at all -- the "DC ON" and "RUN" lights are lit up brightly, and
> the "SR DISP," "BUS ERR," and "MAINT" lights are glowing dimly.  The
> status register display is dark.  The system does not respond to any
> keypresses on the panel.
All LEDs "glowing dark"?
I've seen this, when the 20 pin cable from M7859 to the console panel 
is plugged in reversed.
Don't trust the marked pin 1 wire: sometimes DEC manufacturing twisted 
the cables.

hope this helps,

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