Click Here to visit our Sponsor
The Latest News ! The History of Computing The Magazine Forums Collectors corner Have Fun there ! Buy books and goodies
  Click here to loginLogin Click here to print the pagePrinter ViewClick here to send a link to this page to a friendTell a FriendTell us what you think about this pageRate this PageMistake ? You have mr info ? Click here !Add Info     Search     Click here use the advanced search engine

Ontel

Amigo
Browse console museumBrowse pong museum









 

Back to the roots goodies !

see details
Atari ST bomb icons goodies !

see details
H.E.R.O. goodies !

see details
Commodore 64 boot screen goodies !

see details
Space Invaders - Retro Gamer goodies !

see details
Commodore VIC-20 goodies !

see details
Atari ST bee icon goodies !

see details
www.old-computers.com logo goodies !

see details
Odyssey 2 / Videopac Select Game prompt goodies !

see details
Commodore 64 goodies !

see details
Amiga Workbench goodies !

see details
Odyssey 2 / Videopac sprites goodies !

see details
ZX Spectrum goodies !

see details
Oric Atmos goodies !

see details
Apple II goodies !

see details
1kb memory only...sorry goodies !

see details
Camputers Lynx logo goodies !

see details
Amstrad CPC-464 goodies !

see details
Pixel adventurer goodies !

see details
READY prompt goodies !

see details
Destroy all humanoids ! goodies !

see details
MSX Retro Gamer goodies !

see details
Space Invaders goodies !

see details
I love my Oric-1 goodies !

see details
Horace is not dead goodies !

see details
MZ-700 goodies !

see details







H > HEATHKIT / ZENITH  > H-89     


HEATHKIT / ZENITH
H-89

The H-89 was sold under the two names: Heathkit H-89 and Zenith Data Systems Z-89. The H-89 was sold in kit form, the Z-89 came assembled.

It originally came with 16 KB of memory, later versions provided up to 48KB on the main CPU board (in groups of 1 KB chips). Zenith and Heathkit offered a 16 KB expansion card ($120) for a total of 64 KB when using CP/M.

The system was identical to the H-19 video terminal but had an additional CPU board between the CRT and the terminal board. (Really identical because Heath offered upgrade kits to convert an H-19 to an H-88/H-89 computer).

It used hard sectored disks with a built-in card controller. Under either H-DOS or CP/M, disk capacity was of 90 KB. Another model the H-88 was identical to the H-89, but did not include the floppy drive or controller. It had a cassette port.

A couple of years later, the H/Z-37 soft sectored controller and ROMS came out, then was replaced with a double 5.25" floppy disk drive called H/Z-87 (102 KB, 250 ms). A double 8" floppy disk drive called H/Z-47 (1 Mb each) and a hard disk called H/Z-67, it contained one 10MB 8" winchester drive and one 8" floppy drive (like the one in the H/Z-47).

It ran under HDOS or CP/M (the operating system used 16 KB of RAM).
HDOS was originally written for the H-8, it ran without modification on the '89. This was a single-user OS written by J. Gordon Letwin for Heath. It included a Basic interpreter and assembler.
For CP/M, H/Z wrote a custom BIOS in assembler that the new user could further customize for his specific hardware and assemble right on the machine.
A version of MP/M was also available for the system.

A lot of extension boards were available for this computer including 64 KB memory boards, hard-disk controller cards, 3-port serial I/O board, H19 terminal board, etc.
A third party small upgrade card was also offered which doubled the processor speed to 4 Mhz.

An assembler/debugger was given with the DOS. A paper tape reader was available as well. Microsoft has adapted its various programming languages (Basic, Fortran, Cobol) for this computer. Borland also offered a version of Turbo Pascal that worked great with the CP/M.

Dennis reports:
The base H-89 had no graphic modes, just 33 graphic characters. At least two different add-on boards were created that gave the H-89 bitmapped graphics capabilities, but I'm pretty sure they both required hardware modifications to tie them in to the terminal board - this was not a simple plug-in expansion card


ShareThis


 

I assembled a H89 whilst Principal at an elementary school. Wrote a program to number-crunch attendance for the dreaded Quarterly Report. The Superintendent saw it, and bought a TRS 80 for his needs. Mine was the first. Also played the horse race game on it, and figured out how to rename the horses after the School Board members. Computers for teaching came rapidly after this beginning.

          
Tuesday 25th February 2014
James Starbird (Van Buren, Arkansas)

This was the first computer my father bought so he could research how to do fusion through computer programming. My brother designed a Pacman program on (it was very primitive in the graphics area), and I did writing. It had to be booted up with a disk, and in those days, software did not have backups. One time I was saving a file, and it was too big for the disk, for the computer abandoned it!

          
Wednesday 2nd May 2012
Linda Adams (Northern Virginia)
Linda Adams'' Blog

Wanted this computer. I will pay any postage costs!

megabyte2003(at)list.ru

          
Tuesday 20th March 2012
Sergey (Moscow, Russia)

 

NAME  H-89
MANUFACTURER  Heathkit / Zenith
TYPE  Professional Computer
ORIGIN  U.S.A.
YEAR  1979
END OF PRODUCTION  1983
BUILT IN LANGUAGE  None
KEYBOARD  Full stroke keyboard with numeric keypad
CPU  Zilog Z80
SPEED  2.048 MHz
RAM  From 16 KB up to 64 KB
ROM  Custom bootup & monitor
TEXT MODES  80 chars. x 24 lines ( + one independant line)
GRAPHIC MODES  No graphics mode. 33 graphic characters
COLOrsc  Monochrome green phosphore display
SOUND  Beep - HUG magazine had a article on how to use one of the serial ports as a crude
I/O PORTS  RS232 (two, up to six), Centronics, IEEE 488
BUILT IN MEDIA  90 KB floppy drive
OS  HDOS, CP/M, MP/M
POWER SUPPLY  Built-in power supply unit
PRICE  $1,800 as kit in 1979 w/ 1 floppy drive





Google
 
Web www.old-computersc.com


 

More pictures
Adverts
Hardware Info
Software & screenshots
Documentations
Mini-Forum

Click here to go to the top of the page   
Contact us | members | about old-computers.com | donate old-systems | FAQ
OLD-COMPUTERS.COM is hosted by - NYI (New York Internet) -