6 Mar
2007
6 Mar
'07
6:49 a.m.
While repairing our VT11 that hangs the Unibus as soon as you point the
light pen to the high frequency fluorescent room illumination (which makes
playing lunar lander a pain) I've discovered that the schematics of the
M7014 board (bus control & bootstrap) as found in the GT40 engineering
drawings (from bitsavers) do not correspond to our board (a M7014-YA).
The document number for the M7014 board is D-CS-M7014-0-1.
Does anyone have the document numbered D-CS-M7014-YA-1 in electronic form
(or even the complete VT11 engineering drawings)?
Christian
6 Mar
6 Mar
9:02 a.m.
Hi Christian,
I might be able to help you with this. Is there a # and a goiod time I could
call you?
Paul Anderson
On 3/6/07, Christian Corti <cc at corti-net.de> wrote:
While repairing our VT11 that hangs the Unibus as soon as you point the
light pen to the high frequency fluorescent room illumination (which makes
playing lunar lander a pain) I've discovered that the schematics of the
M7014 board (bus control & bootstrap) as found in the GT40 engineering
drawings (from bitsavers) do not correspond to our board (a M7014-YA).
The document number for the M7014 board is D-CS-M7014-0-1.
Does anyone have the document numbered D-CS-M7014-YA-1 in electronic form
(or even the complete VT11 engineering drawings)?
Christian
1:48 p.m.
While repairing our VT11 that hangs the Unibus as soon as you point the
light pen to the high frequency fluorescent room illumination (which makes
playing lunar lander a pain) I've discovered that the schematics of the
I'm trying to remember something about this, I was working on this device
some 15 years ago...
From what I remember, when the ligth pen is triggered,
it halts the VT11
'processor' (so the corrdinates in the X and Y latches
are the position
of the light pen) and then interrupts the PDP11. The PDP11 reads out the
coordinates and restarts the VT11.
A problem with the interrupt logic (which is much the same as the
interrupt logic on any other Unibus device) could well cause the problem
you're seeing.
M7014 board (bus control & bootstrap) as found in
the GT40 engineering
drawings (from bitsavers) do not correspond to our board (a M7014-YA).
How different is the interrupt circuit? If you trace back from the
appropriate pins on the edge conenctors do you find the same sort of logic?
-tony
6501
days inactive
6501
days old
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