Fastest PDP-11 = SBC Computer Wire-Wrap design1985-86

[Serpico261]

can i ask a question regarding your wire wrap board?

[PDP11GY]

There was no operating system like Unix running . Ony programs written in Micro_Power_Pascal or in MACRO-11 assembler could be downloaded to my system.

[UserNumber3141592653]

Do you run unix on it or vms? (I believe those were the two operating systems used on PDP-11 machines, but I'm also young so please correct me if I am mistaken)

[andh00]

@UserNumber3141592653 The operating systems used on PDP-11 series were: RT11 RSX11 and VMS (and XXDP for diagnostics). The instruction-set of the processor is basically the same as the Motorola 68000 microprocessor

[douro20]

@andh00

But isn't the 68000 actually faster than a J11 or T11?

[stmbaah]

nice video! music also great

[GalaticTG]

4:06

When I got my first 500Mb HDD I though to myself. I'll never run out of space. When I got my first 1Gb Hard drive I though I would never run out of space.

I just bought a 1Tb hard drive and figured it'll be full in a month :D

[TheEPROM9]

@GalaticTG The more space you have, the more shit you fill it with.

[GalaticTG]

@TheEPROM9

True that.

[hadr0n]

But will it run Doom? ;)

[PDP11GY]

@hadr0n No Doom :-)) sorry 

[Serpico261]

@PDP11GY hi there, where do you get this board like you have??

[levogiro]

Please... where did you found the J-11???????

That's a piece of electronics worth being worshiped!

[PDP11GY]

@levogiro The assumtion to get a DCJ-11 chip was very simple. I was a DEC employee from 1977 to 1993, also working for the local PDP-11 engineering team. More infos on my homepage.

[bootnecklad]

It was your videos that helped inspire me to build my own TTL CPU! I am still building it but you can see videos of it so far!

[PDP11GY]

@bootnecklad Wish you good luck and success for your project. It gives me pleasure that I could inspire you !

[cobrachoppergirl]

We use to do the modern day equivalent of clock chiping these things but cutting the wires, and shortening them, to lessen the distance electron impulses had to travel at the speed of light.

[fireofsev]

Was that a Texas Instruments ic on that board? This is fascinating.

[PDP11GY]

@fireofsev It only is close to see a Texas Instruments IC. It's a standard 74xxx TTL chip used in my case to replace the original Clock-Chip.

[PDP11GY]

For me, it was more convenient wire wrapping on the frontside

because trouble-shooting via scope and logig-analyser was easier.The backside was used for Power-distribution. For me, this

wire wrap technique was neatly arranged. For temporary connections,I used daisy-chain cables and the final wire-wrapping was als done with a wire-wrap machine.

[Catalingo]

Very much enjoyed watching this. What especially interested me was your wire wrapping technique. The wire wrapping I usually see is done on the backside, using the socket itself. Would you describe how you did your method?

[kinglonewolf104]

I'm more into Spectrums and Amigas than PDP's, but a cool video nonetheless :)

&eB

[websavvydood]

Takes me back to DEC PDP 11/05 & 11/20 days- OFTEN had to wirewrap/unwrap pins on the Unibus backplane.

Knowing EXACTLY what's involved here, what you've done is no mean feat. Well done - VERY tidy too given that one of the biggest issues is that MOST wirewrap pins will only allow a max of two (rarely 3) wraps per pin.

Not sure this would be fastest PDP/11 tho - that was probably a PDP 11/45 or possibly an 11/60. Also the 11/73 was likely quicker too, but fastest 11/23? Could well be.

[PDP11GY]

Hello, concerning wire-wrap, my experience was that the max of wraps per pin depends from the length of the pin and how many rotations you are using.

[PDP11GY]

Concerning Fastest PDP11, I think you are confused completely. The PDP11/23 series was based on the DEC F11 Chip and my

design is based on the much more fastest DEC J11 Chip. The fastest PDP11's manufactured by DEC was the

11/73,83,93(Q-Bus) and 11/74,84,94(Unibus) running at 10, 15,18 Mhrz. My design would also run with a 18Mhrz J11 chip available, but already running at 15Mhrz is a little faster( 5%) than the fastest DEC-PDP11/93 ! It's nostalgia.

[stephanefr]

No way I'll let you approach my 11/05 with your satanic wrapping tool ! :-)

[GroovyMango]

WONDERFULL!!

[jaesungauzakim]

WoW 2 KByte for $100 in 1985. COOL!

[doseryder]

This is how things are done w/o a PCB?

Wow. This is really what it means to "build a computer". I guess you need to have COMPLETE understanding of every single chip (the I/O pins on each chip and know what they do.) How do you know what the voltage requirements of each chip is? oh well, that's way beyond me.

[PDP11GY]

Yes, understanding of every single chip was one point and relatively simple,

because there is/was a data-scheet via paper or micro-fish available. The most

time consumption part in a project like this was working with scope and

logic analyser.

[chrihern]

wire-wraped uhh... good idea

[dma52691]

wow..... to imagine how long it takes just to get that running just, makes my work stupid easy. im 17 and build custom pcs but its thanks to u guys that makes computers a piece of cake

[oc5nsli341nforce4]

I learned to build systems on post late 80s tech still know to set things up even in the age of quad cores and gxt295, 128gb of ram, four quad cores for grand slam total of 16cores! All = a mean server with the ability to run crysis on high while do every thing else.

[jtel]

That is beautiful.

[PDP11GY]

Thanks ! I have no experience in knitting but it looks much the same. Relaxing ? I disagree .. wirewrapping somtimes was crazy :-))

I did take about 2 yesrs ( 1985-1986) to complete this Computer. Last year , 2007, I only have restored this Computer.

[yanevenu]

Used to love wirewrapping. Relaxing, like knitting for geeks (who don't knit).

Did it take you 22 years to complete this, or are you just restoring an old love?