Adventures with the Nixdorf 8870 Mini-Computer
  • Welcome
  • Contact Me

One thing… leads to another…

8/3/2011

0 Comments

 
As part of the 8870 documentation process, I thought it would be sensible to make copies of all EPROMS and ROMS contained within the hardware (system boards and terminals). Early 8870 hardware often had EPROMS and these can “fade” over time so it’s sensible to have images from known working devices stored safe and sound.

The first place I decided to start was with the EPROMS / ROMS stored in the DAP4 CPU board. However, and there’s always a however with Nixdorf hardware, the EPROMS are actually 2516’s and these use a different pin-out to standard 2716 devices and they also need 25v for the programming cycle; this means my old and trusty EPROM programmer won’t program them, and more of an issue, won’t read them either. I could make an adapter board to allow them to at least be read, but my friend VAXMAN mentioned that he had some 2708 EPROMS he would like to read and these devices are complete pigs to use; they need +5, -5, +12 and +25v and there’s no way my programmer will ever handle these. So I decided it’s time to design and build a new one. Whilst I’m at it, I’m taking the opportunity to build-in some additional features that I’ve always found missing. I want it to be able to handle just about any EPROM available, RAM chips, and be able to be used as a ROMULATOR (ROM Emulator).

Once it’s done, I’ll post the design, PCB foils etc. here for those that are interested. I may even build you one if you ask nicely!!

I’m still hunting around for a NIROS operating system but so far, I’ve not had much luck. I have been in contact with somebody who has a rather large Nixdorf 8870 collection but most of his equipment isn’t currently running and I’ve offered my services to help him get things going. Perhaps we can salvage an op-sys off one of his systems.
Picture
DAP4 being eatern by a leaking lithium battery.
This reminds me… those of you who are holding onto old equipment, Nixdorf, DEC, IBM, whatever, please.. PLEASE make sure that you check terminals for batteries (rechargeable or lithium) and any battery backup systems contained within your main chassis. These batteries leak and do terrible damage if left unchecked. Go on… go check now, you may be just in time to stop one of your system boards being eaten.


0 Comments



Leave a Reply.

    Author

    I'm a software developer, an engineer and I love vintage computers, but the 8870 has a very special place in my heart.

    Archives

    August 2017
    January 2016
    May 2015
    June 2014
    November 2012
    June 2012
    February 2012
    July 2011
    May 2011
    March 2011
    February 2011

    Categories

    All
    1/2 Inch
    2516
    2708
    8870
    9 Track
    ALME
    BASIC
    Boot
    Bootmenu
    Chassis
    Comet
    Confprog
    Connection
    Dap
    DAP4
    Dap Emulation
    Dc600a
    Diablo
    Dicolldata
    Disc Pack
    Disk
    Documentation
    Downloads
    Drive
    Ebay
    Entrex
    Eprom
    Ex
    First Post
    Format
    Formatter
    Freelancer
    German
    Germany
    Hawk
    History
    Ihss
    Init
    Ipl
    Iris
    Junk
    Kienzle 6100
    LIBR
    M25
    Manual
    Micro 7
    Nd11
    Niros
    Nixdorf
    Nros
    Pcb
    Perish
    Programmer
    Programming
    Ram
    Ribbon
    Rom
    Smc
    Start-stop
    Streaming
    Tamos
    Tandberg
    Tape
    TDC3309
    TDC 3309
    Translation
    Ultratec
    Vaxman
    Vdu
    Wd40
    Wireing
    Xlp300

    RSS Feed

(C) Joe Farr, 2011-2017