bmw@aesat.UUCP (Bruce Walker) (03/14/86)
In article <283@ll-xn.ARPA> olsen@ll-xn.ARPA (Jim Olsen) writes: > A note of interest to those of us who knew and loved (:-)) the PDP-8: > DEC is still making them! The 'DECmate' word processor is based on a > microprocessor version of the PDP-8. (You can even run OS/8 on it.) > -- > Jim Olsen ARPA:olsen@ll-xn UUCP:{decvax,lll-crg,seismo}!ll-xn!olsen For those of us masochistic enough to even bother with these early RISC machines, the microprocessor in the DECmate is made in a CMOS process by Harris Semiconductor Corp. and is called the HM6120. It is an architectural extension of the PDP8/e (runs all old code) with two stack pointer registers added (and a few other ying-yangs). If you add an HD6102 MEDIC (Memory Extension & DMA Interface Controller) chip, you can have the FULL (yes folks!) 32K words of memory and a DEC-compatible DMA port. The "original" CMOS PDP8/e is still made by Intersil (since about 1975-6) as the IM6100, and a little kit of parts (processor, UART, 256 words ram, 1K words of rom) can be bought for ~$70 (CAN.) that runs a faithful reimplimentation of ODT. Hmmm, let's see, all I need now is a paper tape reader ... Egads! Do you know it costs less to buy a 10M hard disk than a paper tape reader these days?!? Bruce Walker {allegra,ihnp4,linus,decvax}!utzoo!aesat!bmw "I'd feel a lot worse if I wasn't so heavily sedated." -- Spinal Tap
zemon@fritz.UUCP (Art Zemon) (03/21/86)
The PDP-8 not only lives, it refuses to die.
I have a real, honest to goodness, still WORKING, original
Digital Equipment Corporation PDP-8 in my den. For those of you
who are religiously familiar with the 8 line, this is simply a
PDP-8, not an 8L or 8E or anything.
For the rest of you, this is what a "real" computer is like:
The PDP-8 predates integrated circuits. It is made of about a
zillion Flip-Chips (TM or something by DEC) each housing gobs of
discrete transistors, diodes, and other goodies. For example,
the accumulator is made up of twelve double Flip-Chips, each
implementing one BIT! Each one of these boards is roughly one
half the size of a normal CRT screen.
The PDP-8 has a box roughly ten inches cubicle which contains
four kilowords of core. Now this is not four kilobytes nor is
it eight nor is "core" a euphemism. The 8 has 4096 twelve bit
words of real magnetic doughnuts with wires strung through them.
This stuff, if my memory serves, cycles at the blinding speed of
1.5 milliseconds.
Physically, this machine is straight out of a science fiction
flick. It is about three feet cubicle with the top two feet
covered with smoked Plexiglass. The bottom foot of the front
panel has a row of toggle switches all the way across it and
enough lights (incandescent, not LEDs) to keep Santa happy.
But the best part is turning it on when the gas is out on a cold
winter night. It blithely consumes 780 watts of power and the
six fans swirl it around the entire house just fine. But they
don't blow the thing over; it weighs in at 250 pounds.
If you compare the "Classic-8" to one of these new fangled
68020s or RISC machines, you'll have to agree. For sheer
presence and class, the PDP-8 is unsurpassed in the Mini-
Computer market. Beg to differ? Lets try a little contest.
You put your computer on top of mine for an hour and well see if
my PDP-8 still runs. Then....
Cheers,
--
-- Art Zemon
FileNet Corp.
...! {decvax, ihnp4, ucbvax} !trwrb!felix!zemoncdl@mplvax.ARPA (Carl Lowenstein) (03/24/86)
In article <465@fritz.UUCP> zemon@fritz.UUCP (Art zemon) writes: >The PDP-8 not only lives, it refuses to die. > >discrete transistors, diodes, and other goodies. For example, >the accumulator is made up of twelve double Flip-Chips, each >implementing one BIT! > >The PDP-8 has a box roughly ten inches cubicle which contains >four kilowords of core. >This stuff, if my memory serves, cycles at the blinding speed of >1.5 milliseconds. -- carl lowenstein marine physical lab u.c. san diego {ihnp4|decvax|akgua|dcdwest|ucbvax} !sdcsvax!mplvax!cdl
cdl@mplvax.ARPA (Carl Lowenstein) (03/24/86)
In article <268@mplvax.ARPA> cdl@mplvax.UUCP (Carl Lowenstein) writes: >In article <465@fritz.UUCP> zemon@fritz.UUCP (Art zemon) writes: >>The PDP-8 not only lives, it refuses to die. >> >>discrete transistors, diodes, and other goodies. For example, >>the accumulator is made up of twelve double Flip-Chips, each >>implementing one BIT! > These are nowadays called bit slices.> > >> >>The PDP-8 has a box roughly ten inches cubicle which contains >>four kilowords of core. >>This stuff, if my memory serves, cycles at the blinding speed of >>1.5 milliseconds. > That's 1.5 *micro*seconds which is not too bad for 1963 technology.> > I don't understand how my first attempt got out without the added comments. Sorry about that. -- carl lowenstein marine physical lab u.c. san diego {ihnp4|decvax|akgua|dcdwest|ucbvax} !sdcsvax!mplvax!cdl
tuba@ur-tut.UUCP (Jon Krueger) (03/26/86)
In article <465@fritz.UUCP> zemon@fritz.UUCP (Art zemon) writes: >The PDP-8 has a box roughly ten inches cubicle which contains >four kilowords of core. Now this is not four kilobytes nor is >it eight nor is "core" a euphemism. The 8 has 4096 twelve bit >words of real magnetic doughnuts with wires strung through them. >This stuff, if my memory serves, cycles at the blinding speed of >1.5 milliseconds. It cycles at 1.5 microseconds. Let's not exaggerate.