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NDR Klein Computer (NKC) [message #2148] Thu, 30 March 2017 07:02 Go to next message
creep is currently offline  creep
Messages: 17
Registered: April 2016
Location: Germany
Junior Member
Hello,

this topic will surely be more attractive for the German speaking members.

In the early 80's, there was a computer related education TV show on German television, introducing the micro computer designed by Rolf Dieter Klein and building this together with the TV viewers. Here are the videos:

http://www.ndr-nkc.de/compo/doku/videos.htm

In the beginning, this was a simple Z80 computer with a very modular system: BUS, CPU card, memory card, graphic card (with EF9366 controller), keyboard card, ...

Also Floppy controller, bank switching (for CP/M), sound (AY-chip) etc. was added. Due to the modular concept, even 68k processor card and 8088 was possible.

The best introduction you can get is in the copy of the author's second (updated) book:

http://www.ndr-nkc.de/download/books/buch_rechner_modular.pd f

There are also web pages and still forums dealing with this system:

http://schuetz.thtec.org/
http://www.ndr-nkc.de/compo/index.htm
http://schuetz.thtec.org/forumdrc/index.php

When I was a child, I was following the TV show and was fascinated. But in East-Germany, there was no chance to build this computer.

Recently, I checked again and noticed, that there are still users and new projects. But there was no source to still get the PCBs. And the PCBs in the book are only printed in poor quality.

So I started and newly created the layouts drawing the original pictures in Sprint Layout 6. Later I improved the layout, added capacitors the chips, connected unused inputs to allow the usage of HCT chips and other minor improvements.

I only wanted to do this for myself and maybe give away the not needed PCBs from Chinese production. But when I announced this in the (former East-German) Robotrontechnik-Forum

http://www.robotrontechnik.de/html/forum/thwb/showtopic.php? threadid=14374&time=1490880726&s=936cfcc3010f5044ced d2b5e279ebbfe

the response was overwhelming. Since then, I completed

BUS - BUS system PCB
Z80CPU - processor PCB
ROA64 - EPROM/RAM PCB

and am very close to completing

GDP64 - Graphic
KEY - keyboard adapter
SOUND - no explanation necessary

another member joined and will soon complete

FLO3 - Floppy controller
BANKBOOT - memory switching

At DirtyPCB, I ordered more than 300 PCBs for the first components and most are already distributes. Final price is ~4...8 Euro per PCB, because I do this as a hobby and don't want to make any profit.

Currently I am collecting reservations for the GDP64 graphics card.

If any of you are interested in this project, please go to the Robotrontechnik-Forum and join the thread. Or contact me directly. It is still time to reserve GDP64 and following cards. And for sure, there will be a new production of the PCBs. AND: I distribute all layout files, so everybody can then improve these or re-order.

First two can be found here:

http://schuetz.thtec.org/NKC/doku/layout/layout.html

or here

http://dirtypcbs.com/store/designer/browse/10727

http://www.robotrontechnik.de/bilder/Upload_Forum/1n8_mno.jpg

After having fun with the multicomp, this project was some kind of a childhood dream.

Rene

[Updated on: Thu, 30 March 2017 07:04]

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Re: NDR Klein Computer (NKC) [message #2160 is a reply to message #2148] Thu, 30 March 2017 11:38 Go to previous messageGo to next message
Jonas is currently offline  Jonas
Messages: 63
Registered: October 2015
Member
Vielen Dank, Rene!

This is really fascinating! Nostalgia and a lot to learn. This is also a good opportunity to improve my Deutsch. I'm going to Berlin in April.

Jonas
Re: NDR Klein Computer (NKC) [message #2164 is a reply to message #2160] Thu, 30 March 2017 14:12 Go to previous messageGo to next message
mikemac is currently offline  mikemac
Messages: 175
Registered: March 2017
Senior Member
Yes, quite interesting. I snagged a copy of the book even though I don't read German. Most of it I can make a reasonable guess at what it's talking about. And for the most part, a schematic is a schematic.

The whole thing kind of me reminds me of the much more recent RC2104 Z80 series.

Thanks for the info!



Mike
Re: NDR Klein Computer (NKC) [message #2177 is a reply to message #2164] Fri, 31 March 2017 03:53 Go to previous messageGo to next message
tor is currently offline  tor
Messages: 25
Registered: April 2016
Location: Norway/Japan
Junior Member
Very interesting! Thanks for posting. I downloaded that book and skimmed through the first 250 pages. The book is fantastic! It covers everything from beginner's electronics to digital and logic, advancing quickly to practical stuff. Later there's programming and much much more.
A modular setup like that, with the potential for bank-switched memory (would work with CP/M 3 I suppose) is something I'm interested in.
Re: NDR Klein Computer (NKC) [message #2179 is a reply to message #2177] Fri, 31 March 2017 04:11 Go to previous messageGo to next message
creep is currently offline  creep
Messages: 17
Registered: April 2016
Location: Germany
Junior Member
Yes, the really strict modular concept is what makes this project interesting. If you have an SBC or some retro computing system, you usually have to consider the already used I/O ports or memory addresses. With this one, you are really flexible. In theory, you can plug in any extension card from an 80s home computer and make it work. Maybe, I will even try to use the Cyclone2 board from the multicomp and use it as a replacement for the Z80CPU PCB. Just for fun. My favorite wish would be to use this FPGA board a a graphics card with VGA output on the NKC BUS.

When I re-design the PCBs from the book, I also try to do some improvements. E.g. the original IOE I/O card did not have full address decoding, this will be changed. Currently, I'm doing the SOUND PCB. The book is using the AY-3-89-12, but the AY-3-89-10 is available easier and has two parallel ports (not really needed). My design will allow to place any of them and also includes the mounting of an PAM8403 amplifier board (<$1) with jumper configuration of the three sound channels to the L/R.

It's a lot of fun and a good project to learn Z80 from scratch. I also plan to add real Z80 PIO/SIO/CTC, even this was not used in the book.

If you are interested, just follow the links above. I will distribute all PCB layouts when ready and tested.

Rene

[Updated on: Fri, 31 March 2017 04:20]

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Re: NDR Klein Computer (NKC) [message #2821 is a reply to message #2179] Thu, 18 May 2017 08:15 Go to previous messageGo to next message
creep is currently offline  creep
Messages: 17
Registered: April 2016
Location: Germany
Junior Member
Hi,

meanwhile, the project grew and already contains sound board, I/O board, floppy controller and bank switching for CP/M as well as a "big" BUS with 12 slots.

You can find the (verified) layouts here, the rest will come soon:

http://schuetz.thtec.org/NKC/doku/layout/layout.html
or here
http://dirtypcbs.com/store/designer/browse/10727


But I have a question:

As already mentioned, my plan is to make a PCB to plug the well known Chinese Cyclone II development board into this NKC bus system. To use the FPGA as CPU or VGA-board, SD-card controller or any combination mixed with the "real" components.

The FPGA is a 3.3V system, the Z80 bus 5V. What is the best way to connect these two worlds? Just put a 74LVC245 or 74LVC16245 between FPGA and BUS for all data-, address- and control lines? Did anyone here already try something like this?

Best regards,
Rene
Re: NDR Klein Computer (NKC) [message #2894 is a reply to message #2821] Wed, 24 May 2017 13:34 Go to previous message
fritzeflink is currently offline  fritzeflink
Messages: 67
Registered: January 2017
Location: germany
Member
for information only

some information is here too - of course in german language.

http://oldcomputers.dyndns.org/public/pub/rechner/ndr-mccpm/ manual/RDK/index.html


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