4 Oct
2015
4 Oct
'15
8:58 p.m.
On 10/04/2015 01:09 PM, Henk Gooijen wrote:
Some corrections to my post regarding the console LED
behavior.
Voltage levels on the CPU backplane are still good whne
the 2 CPU boards
are installed in the backplane, but the processor is not
responsive to
the switches on the console panel.
The RUN LED is on, ADDRESS/DATA are all off.
You have no memory, and probably no
devices to complete the
Unibus. So, it is quite likely showing the Unibus is in a
jammed state. At the least, you need a Unibus terminator,
and any bus grant cards between the CPU and the terminator
(you'd have to check the manual to see how the Unibus is wired.)
Jon