Tuesday, May 14, 2019

Backplane "Mapper" (DG Nova, DCC D-116 & Entrex 480/Nixdorf 620)

This is a crazy project that I'm just muddling my way through with sheer ignorance and determination.

I want to test every connection in every slot of the backplane of Dominique's Entrex 480/Nixdorf 620, since it is the only known surviving system of its kind in existence, and then reverse engineer the thing from the center outward.

So, here's the backplane "adapter board" design...
Click to download the Gerber files

And here's my schematic on how I'm going to use an Arduino (I know...can't I do better??!!!) to test each and every connection in each slot I plug the set into.

Yes, there are so many things wrong with it...I know...
Click to see full-size schematic

I even asked for help here on Upwork:

But I haven't hired anyone yet...

Here's the text from the job post...

Wednesday, May 8, 2019

Digital Computer Controls - D-116 16-Bit Computer Handbook - 1972

Well, since the Entrex 480 / Nixdorf 620 system clearly has a D-116 as it's processor, it seems that acquiring this manual was a priority...so we did!

Vintage Digital Computer controls - D-116 16-Bit Computer Handbook - 1972

For comparison, Dominique's Nixdorf 620 processor label