Running A PDP-8 From 1965

#franlab #computer #history
- Music by Fran Blanche -

[markshaum]

I love this! My introduction to Octal arithmetic was on a PDP-8e. Fun toggling in the boot loader to give it enough smarts to read the tape reader.

[reasonablebeing]

Early computer goodness - I have a magnetic core memory plane from a Russian PDP-11 clone in my technology tchotchke display case. I am older than the PDP-8 but some days my memory core plane seems to be less than 4K.

[TokenRing]

I was a graduate student in Electrical Engineering at North Carolina State University when the department obtained a PDP-8, This was the first "personal computer" on campus and it was my responsibility. This was before there was a Computer Science department on NC State. I developed some demonstrations / lab exercise around it for EE students. I also used it to simulate a learning machine for my dissertation. Found Memories.

[LunaticEdit]

You literally can't create enough of these videos. These are the coolest freaking videos on YouTube!

[jdedourek]

Spent many hours with a fellow grad student, Paul, working on one of these in the latter part of the 60's. We were using it as a graphics front end controller attached to a PDP-10. One day Paul yelled: "Hey it's on fire!" Sure enough, there was an evident candle flame behind the plastic front panel. We pulled it open. A carbon resistor near the key switch had decided to burn out spectacularly. It didn't last long. Service man replaced it and all was good again.

[basinstreetdesign]

I cut my teeth in programming a PDP-8 in 1967. Our high school was the only school in Ottawa, Ontario to have its own computer then. It was completely refurbished by an electronics teacher then, Mr Weik, who had worked on the famous Avro Arrow fighter jet before it was cancelled and scrapped. I was one of the then few computer hackers at that school. We used lots of paper tape as the storage medium. It was a blast.

[bobhart]

My high school had a pdp 8. In 1975. I learned how to program in basic, we stored our programs on paper tapes.

[trainliker]

An interesting aspect of the PDP-8 12-bit architecture is that it was implemented in an early microprocessor - the Intersil 6100 of 1975 (and later made by Harris). This was also implemented in low power CMOS making it the first low power microprocessor. At about the same time the RCA 1802 (COSMAC) came out and, for a while, these two were the only low power general purpose ones available. I designed a low power data logger as part of a system and had only the 6100 or 1802 to choose from. I opted for the 1802 with its pretty unusual architecture compared to most other processors. And some of its features appealed to me. Also, the OTHER manufacturers of microprocessors kept saying, "We will have a low power version next quarter." But they didn't. Quarter after quarter went by and turned into years. So, used the 1802 for a long time and then after other low power alternatives were on the market for a couple of years, did another comparison and switched to the 8051 family (and was very happy with it).

[mrspockal]

PDP-8 literally changed my life. In college during early 1970s, got my first introduction to programming on a PDP. Learned assembler and an interpreter language called Focal. I was hooked. So what does a math major do for a career - become a computer programmer / systems analyst.

[markurban]

I've got a PDP-8E down in my garage, probably a couple of boxes of parts and a set of manuals, too.

[Madness]

Before it went under, the Computer Museum, in Boston, sold those "flip-chips, " loosely, in their gift shop. But it wasn't until later years that I took interest in what they were actually used for. Back then, they were just a cool novelty.

[robainscough]

Awesome, first computer I programmed on was a PDP-11.

[daffyduk]

Many TTs had an attached paper puncher/reader. My first ever DEC BASIC programs were stored on paper tape for convenience (short progs). Super 'puter, the ultimate "blinkenlights" m/c which didn't need it's own apartment & associated 3-phase a/c

[scottthomas]

I'm glad there are people out there keeping these old computers alive...sort of expected the computer to play " Daisy"..

[mikebarushok]

The music program was one of the first things I did when I had a Mark-8 microcomputer. Except I did input from a "keyboard" from a row of momentary contact micro switches. 1st version used single bit output to a speaker through a capacitor. 2nd version justed used the emitted RFI into any nearby AM radio.

I only had front panel switches to input programs (in binary). Later I built an Octal keypad and display for faster programming. Good memories.

[lmantuano]

Ah! the "straight Eight"..!!
I had one in my patch at Milan Polytechnic University..
As a DEC FS Engineer in the early 70's, it was my duty to do monthly PMs (Preventive Maintenance - sometimes Provocative ) where lots of fans and console filament light were replaced..
Also got to upgrade the memory from 4k (not bytes but 12-bit words) to 8K. Easy right?
Not so, I add a bunch of red single height boards (the logic) another bunch of green board (the analog stuff) and the actual 4k core stack..
Plug and Play? not so, get out my Tek 465 scope with a current probe, run the memory diagnostic (paper tape loaded from the console Teletype) and watched this particular signal waveform (Inhibit current?) shape and amplitude while adjusting a little pot on one of the green boards.
I remember taking me a while as I really didn't know what I was doing, but I did it! Such fun!
I have really fond memories of all those "eights, -I, -L, -S and finally PDP8-A which earned me a whole week training in Paris,
thankyou DEC!!
lm

[timradde]

Excellent video. I had several pdp-8s between 2000 and 2010. But had to sell all of them as I was moving across the country. So this is a nice way to reminisce.

[ghrey]

I’ve got an old PDP-11 that needs restoration. This kinda encourages me.

[darylmorning]

Gives me warm fuzzies to see the vintage computers still welcoming people to our labs, wish it was in mine. 😀

[OldBaloo]

Nostalgic video! The Russian-made clone of the PDP-8 was the first "personal" computer I was working with.
Great video Fran! Thank you!