26 Jul
1997
26 Jul
'97
7:42 a.m.
1st: (the biggie) VAXStation 3520. 'Cube'
configuration, apparently 4
processors
Four processors would make it a 3540...
, 64meg of ram, a TK70 and controller, one board that
appears to
be the interface between the processor bus and the three Q-bus slots in
the chassis,
How much stuff is on the QBus adapter board? There were two versions: FTAM
supports only the TK70 controller (is you TK70 attached to QBus or to SCSI?)
and FQAM supports any random QBus module.
FTAM is a simple module containing only a few chips; FBIC (interface to the
backplane) and CQBIC (CVAX -> QBus adapter) being the only really big ones.
I believe there was also a clock generator chip, but not much else.
FQAM is chuck full o' goodness. It his a prom-based microcode machine to
run the module and lots and lots of PALs.
and a board on the processor bus marked "I/O
Module" with two
50 pin headers on it.
The connector which goes out the side of the backplane is SCSI. Although DEC
used the DSSI chip on this module, they only supported SCSI; the DSSI chip is
capable of doing both.
The connector which comes out the front of the backplane goes to a distribution
panel which provides:
- Four serial ports (console/printer, modem, mouse, keyboard)
- Ethernet (AUI and BNC)
- Diagnostic code display (one 7-segment LED)
Unfortunately, I don't know the pinout of the cable; I don't have a printset
for the 3520.
There also appears to be a space for what looks like
it would have been a
three board video sub-system (which has been removed).
Three boards is correct. For extra fun, it has its own embedded MicroVAX II...
Aside from the basic power/control cabling, and the
cable to the TK-70,
there are no other cables in the unit at present. (and no place to plug in
a terminal!)
The terminal plugs into the distribution panel which plugs into the I/O module.