29 Jun
2000
29 Jun
'00
7:42 a.m.
8088 CPU clocked at 5MHz
128k DRAM on the motherboard
4 expansion slots, 50 pins each
3 6522 VIAs on the motherboard, for system control functions, the
Printer/GPIB port and the user port
Sound I/O using a 6852 and a CODEC chip
A strange video system. There's 2K*16 bits of video RAM, with a 6845 CRT
controller to address it. The output of that partially provides the video
attributes (intensified, etc). But 11 bits are fed to the address lines
of the main DRAM array. This DRAM acts as the character generator and
stores the bitmap patters for the characters. Note that as there are
2000 characters on an 80*24 screen and 11 bits gives 2048 different
values, it's possible to have a different 'character' displayed at each
screen location, thus allowing a bitmapped display. FWIW, the UK Apricot
computer has a similar video system
IIRC, the Victor 9000 was designed by Chuck Peddle, the
architect of the 6502 (or maybe it was the 6500) processor.
This might account for the Motorola/Mostek chip usage.
2 full-height 5.25" floppy drives on the front.
These are Tandon
mechanims without their logic boards. They're linked to a controller
board that uses essentially the same GCR encoder/decoder as the Commodore
8050, etc. The drives are variable speed units (!) with an 8048 on the
floppy controller board to control the speed. Thes means the machine
manages to get 500K on a single-sided 80 track floppy disk
Not only were they GCR recorded (and I'll probably get this backwards),
the drives were run in a Constant Linear Velocity mode, rather than
the Constant Angular Velocity mode used by most drives. IIRC, the
Mac 400k drives, were also CLV , but weren't GCR.
IIRC, later models used some more compatible scheme; speaking of
compatibilty, there were two variants of Microsoft BASIC available,
one which was either generic or Victor-specific, and another that
was IBM compatible.
Software control of the brightness and contrast of the
(monochrome)
monitor using 3-bit resistor ladder DACs hung off the system VIA.
Does that sound like a Victor 9000?
Oh, yeah, that's it. The thing I remember most is that the
Developer's kit the owner had came with PMATE:
Phoenix-Mike Aronson's Text Editor. I pirated it, then when
I went to my next fulltime job, they had the CP/M version,
which was configurable (using PMATE macros) for different
video systems or terminals, so I was able to combine the parts
to get a version working on a PC when I went to the _next_
job.
Which I used for about 6 months, then I bought a licensed
copy, which I still use as my preferred editor to this day.
For those that are unfamiliar with PMATE, it's more or less
TECO with an incremental redisplay grafted on to it. In other
words, EMACS without the LISP. Not quite, but a reasonable
comparison.
Anybody know anything abut Mike Aronson? Nobody at Phoenix
can tell me *anything* about PMATE, and it would be nice to
have the source code so I could fix some bugs.
-doug q