Today's acqisition here is a TI DS990 Model 1 Intelligent Terminal.
This designation appears to be a complete misnomer as it is in fact a
full
microcomputer. The case appears to be laid up in fiberglass from the
same
mold as a TI 820 KSR, and the logic bus has 86 pins, which I recall
from other terminals of the late '70s, but it has a 3 Mhz TMS9900
processor
(nice BIG white ceramic JDL part with gold pins), 64K of ram (4116's,
plus parity),
a TMS9900 based I/O controller board, 2 asych serial cards, floppy disk
controller, and a VDU controller. Going by the configuration table on
the back
of the case there were other options available as well, including
"GPH",
which I am wondering whether might be some sort of bit-mapped graphics
display. The backplane has a total of 12 slots, 7 occupied. There are
what
appear to be 3 serial connectors on the back of the case, but they do
not
connect directly to the serial cards. They go through the bus
apparently.
I've never had my hands on an 820, but I don't think they're this
elaborate,
and the 911 VDT's I have certainly aren't. Nice hefty modular 200W
linear
power supply with its own bus, too. This particular unit has seen some
rough
handling at some point, and is missing a few keycaps, but it is clean,
and
powers up. There's a nice raster on the screen, but no cursor.
Apparently
it must boot off a disk. There's a 25 pin connector on the back of the
case
which must be for a cable to a FD800/1000 dual 8" drive (which I don't
have
yet). The "IDLE" and "EXEC" lights on what amounts to a minimal front
panel on the keyboard light up, but that's it. No "ERR", anyway.
Somebody
please correct me if I'm wrong, so I can track down the problem.
In actual use, from what I was told, it was probably hooked up by modem
to
Tymshare, the predecessor of Tymnet, and thence to a central facility.
It has
lttle bezels on the front shoulders of the case that identify it as a
Tymshare
Travel Business System BS2000. As an aside, I did a little searching,
and
apparently MCI/Worldcom is still running Tymnet, now on rackmount
Sparc-based nodes rather than the earlier PDP-10's.and M68K's (I
preferred Telenet for X.25; they were always a year or two ahead on
dial-in speeds where I was.)
Anyway, if anyone has manuals or software, in particular a bootable
system
disk, for this machine, I'm all ears. Likewise, if anyone has any
questions
about it, I'll do my best to answer them.
jbdigriz
--
----------------------------------------------------------------
DragonsWeb Labs - Custom R&D, Software, & Hardware
----------------------------------------------------------------
Tagline for Tuesday, February 22, 2000
If rabbits feet are so lucky, what happened to the rabbit?
----------------------------------------------------------------
James B. DiGriz - jbdigriz_at_dragonsweb.org - (912) 653-5139
----------------------------------------------------------------
Received on Tue Feb 22 2000 - 17:40:04 GMT