The LSI-11 is "out of the loop" in this case. The DRV11-WA can take over
the Q-bus and hold off the processor while it reads or writes memory
locations. That gives you the ability to deposit and examine stuff in
memory without the processor involved. Next the LSI-11 does honor the BHALT
state which gives you a run/halt capability and of course reset as well.
What we're missing is a way to load the PC on the LSI 11 externally, but we
can do some of that using an interrupt vector and by manipulating one of
the vector locations to have the PC where you want the system to start.
Yes, its a kludge on a major scale, but its blinkenlights :-)
--Chuck
At 12:56 PM 5/12/01 -0400, you wrote:
>Perhaps the
coolest thing I've seen so far is that you can almost use
this
>thing to create a front panel for an LSI-11
system. You can certainly
>deposit and examine memory and start and stop the processor :-)
Really? LSI-11 never stops, it idles in a microcode loop. Also LSI-11
has
microcode ODT, that is the front pannel.
Allison