>
> On Wed, 19 Mar 1997 18:00:03 GMT, Tony Duell mentioned:
>
> > Do you count PERQ workstations as minis? The CPU is somewhat similar
> > to minicomputers of the time, although extra hardware was added for
> > the rasterop machine (bit blitter).
>
> I confess an absolute ignorance of the PERQ machinery. I've never
> even seen one.
I must enlighten you, then - they're very nice machines IMHO, but then, as
a PERQ-fanatic, I'm biased :-)
They were IMHO the first commercially-sold graphics workstations. The PERQ
1 came out in 1979, and had the following features :
CPU :
20 bit ALU path, with 16 bit path to main memory. ALU also used to
calculate the 20 bit (word) addresses for the main memory
256 20 bit general purpose registers (that is not a typo), 16 level 20 bit
expression stack.
4K writeable control store, with 2910 sequencer chip. Microcode loaded
from disk (normally) at boot-up.
Rasterop machine (bitblitter) graphics accelerator. Uses barrel shift from
main CPU logic + PROMs to implement bitblit operations. CPU calculates
memory addresses, while rasterop logic performs the actual updates.
Capable of more than 10 full-screen updates per second.
Memory/video
64 bit wide (interally) memory board, with 16 bit path to CPU. Also 64 bit
path to video shift registers. Video was 768 (horizontal) * 1024
(vertical) bitmap. Memory was word addressed and varied from 256kB to 2MB
Monitor was a 15" (approx) portrait unit.
I/O
RS232 port, IEEE488 port, keyboard, sound (PCM Codec), 8" floppy drive
controlled by a Z80 + 1K RAM + ROM, communicating with the main PERQ CPU
via an array of FIFOs. 24Mbyte 14" Shugart SA4000 hard disk with own
controller. DMA engine between Z80 FIFO, hard disk controller, and
optional peripherals and main PERQ memory. Optional networking (initially
some PERQ custom thing, later Ethernet), 16 bit parallel link (compatable
with DEC DR11-A) and laser printer (initially Canon LBP-10, later Canon
CX-VDO).
Pointing Device
Summagraphics bit pad one tablet, connected via GPIB interface
Software
Initial operating system was POS (PERQ Operating System), which used an
enhanced pascal as the system programming language. The machine code was
called Q-code, and was an enhanced p-code in many ways. POS was
single-user, single tasking, but supported some basic window operations,
pop-up menus, etc.
PNX was a version of Unix, ported to the PERQ by ICL (who sold the machine
in the UK). It was basically version 7, with a bit of Sys3 added on top.
It had a window manager, called WMS, which feels a bit odd, but which was
(I think) the first such system.
The hardware was built from entirely standard ICs (TTL + PROMs, mainly),
and fitted into a deskside case.
About a year later, the PERQ1a arrived. This had a revised CPU board with
16K of writeable control store (addressed as 4 off 4K banks for
compatability reasons), multiply/divide hardware, and some more hardware
instructions. Many PERQ1's were upgraded to the 1a specification (just a
CPU board swap).
Then came the PERQ 2T1. This used the same (16K) CPU and memory boards,
but had a revised I/O board. This had 2 serial ports, keyboard interface,
sound (same as the older board), 8" floppy controller and a real time
clock controlled by the Z80. The Z80 now had 16K of RAM, and you could
download programs into the RAM and run them on the Z80. The hard disk
controller was modified, and now controlled an 8" micropolis 1203 hard
disk. You could fit the PERQ 1 option I/O board (laser printer, second
ethernet, 16 bit parallel). The cabinet design was also changed, the
keyboard became a VT100-layout one, and the Summagraphics bit pad was
replaced by a custom electomagnetic one (called a Kriz tablet, after the
designer)
The next machine as the PERQ 2T2. This was the same machine as the 2T1
(new cabinet, new I/O board) but used a standard ST506-interfaced hard
disk. Various models existed, with different hard drives. Both Portrait
(768*1024) and landscape (1280*1024) models exist.
The last of the classic PERQs (as this family is often known) was the PERQ
2T4. This had a 24 bit CPU (instead of the 20 bit one in all other models)
and 4MB of RAM, in theory expandable to 32MB. Otherwise it was identical
to the 2T2. I am told that _very_ few were made, though.
That was the end of the classic PERQ line. The name was carried on by ICL
for a short time, who made the PERQ 3000 (aka PERQ 3a) AGW (Advanced
Graphics Workstation). This came out in about 1987 and was a 68020-based
unix workstation with a custom graphics accelerator based on a pair of
AM29116 ALUs and 4K of control store. The rest of the machine was fairly
standard, using standard peripheral ICs. I am told that, again, very few
of these were made.
If you are interested in these machines, try posting to alt.sys.perq,
where we have very few flames (other than for spam, totally off-topic
posts and idiots who ask why we still bother with these old machines).
Feel free to ask introductory-level questions - hopefully somebody there
will answer you.
> Posted information might be interesting to the gathered assemblage.
I hope the above is interesting. Feel free to ask for more details.
> | Carl Richard Friend (UNIX Sysadmin) | West Boylston |
--
-tony
ard12_at_eng.cam.ac.uk
The gates in my computer are AND,OR and NOT, not Bill
Received on Wed Mar 19 1997 - 12:54:34 GMT