website/content/museum/heathkit-zenith-h-89.md

title, categories, types, origins, years, cpus, params

title	categories	types	origins	years	cpus	params
HEATHKIT / ZENITH H-89	Computers	Professional Computer	U.S.A.	1979	Zilog Z80	name image company company_name specs tabs forum_thread photos adverts hardware screenshots oc_id source H-89 /media/museum/photos/h89.jpg /companies/heathkit-zenith HEATHKIT / ZENITH label value NAME H-89 label value MANUFACTURER Heathkit / Zenith label value TYPE Professional Computer label value ORIGIN U.S.A. label value YEAR 1979 label value END OF PRODUCTION 1983 label value BUILT IN LANGUAGE None label value KEYBOARD Full stroke keyboard with numeric keypad label value CPU Zilog Z80 label value SPEED 2.048 MHz label value RAM From 16 KB up to 64 KB label value ROM Custom bootup & monitor label value TEXT MODES 80 chars. x 24 lines ( + one independant line) label value GRAPHIC MODES No graphics mode. 33 graphic characters label value COLORS Monochrome green phosphore display label value SOUND Beep - HUG magazine had a article on how to use one of the serial ports as a crude label value I/O PORTS RS232 (two, up to six), Centronics, IEEE 488 label value BUILT IN MEDIA 90 KB floppy drive label value OS HDOS, CP/M, MP/M label value POWER SUPPLY Built-in power supply unit label value PRICE $1,800 as kit in 1979 w/ 1 floppy drive photos adverts hardware software 147 title subtitle text image H89 AND H77 FD UNIT Complete Heathkit H89 system with the H77 F.D. unit and the Heathkit H-14 serial printer. The H77 unit had a storage capacity of 150 KB x 2. This configuration allowed a system disk to be installed in the H89 integrated floppy and data disks in the external unit drives. /media/museum/photos/heathkit_h89_h89-h77_1.jpg title subtitle text image THE PERFORATED RUBBON READER it can read 50 characters / second and write 10 characters / seconds /media/museum/photos/rub_h11.jpg title subtitle text image H/Z-67 HARD DISK UNIT It contained one 10MB 8" winchester drive and one 8" floppy drive /media/museum/photos/p_z891.jpg title subtitle text image Z-47 (8'' FDD) /media/museum/photos/p_z892.jpg title subtitle text image THE H19 / Z19 TERMINAL This terminal is simply a H89 system without the logic CPU board and disk storage. It was called Heathkit H19 in kit form and Zenith Z19 in assembled form. It could be connected to any system via a serial connection. /media/museum/photos/heathkit_h19_terminal_1.jpg title subtitle text image UNOPENED KIT When a customer ordered a H89 in kit version, he received five boxes. The 5th. one holded the case, floppy disc drive and manuals /media/museum/photos/heathkit_h89_kitunopened_4.jpg title subtitle text image DUST COVER /media/museum/photos/heathkit_h89_dustcover_1.jpg title subtitle text image 1979 RANGE ADVERT Advert shows: - the **WH89** computer ($2295)\ - the **WH11A** 16-bit computer, DEC PDP 11/03 compatible ($1895)\ - the **WH19** video terminal ($995)\ - the **WH26** dual floppy disc system ($2595)\ - the **WH14** serial printer ($895) To note: in 1979, the company name was **Heath Schlumberger data systems.** /media/museum/pubs/heathkit_h89_pub_2.jpg title subtitle text image 1980 RANGE ADVERT Advert said: Choose from three computer systems:\ The H-89 All-In-One Computer gives you everything in one compact, convenient unit.\ The flexible H8 gives you the freedom to combine memory and interfacing for exactly the system you require.\ And the powerful H11A gives you 16-bit power for your most complex programs.\ The Heathkit line includes video terminals, matrix and letter quality printers, and accessories. You'll even find award-winning self-instruction packages to teach yourself programming in Basic or Assembly. /media/museum/pubs/heathkit_h89_pub_1.jpg title subtitle text image 1982 HEATHKIT CENTERS /media/museum/pubs/heathkit_h89_pub_3.jpg title subtitle text image HEATHKIT CENTERS #2 /media/museum/pubs/heathkit_h89_pub_4.jpg title subtitle text image HEATH 19 TERMINAL (1982) $595 was the price in kit form, F.O.B. Benton Harbor...\ The assembled version, called Zenith Z-19, costed $895. An expensive price, not compatible with a home computer budget. /media/museum/pubs/heathkit_h19_pub_1.jpg title subtitle text image FRENCH ADVERT (JAN. 1982) "Adopt a little gifted" /media/museum/pubs/zenith-heathkit_h89_french-pub_1.jpg title subtitle text image EXTERNAL DRIVES Here is a H89 with Hard and Soft Sectors floppy-drives, along with hard-disk drive at the bottom.... /media/museum/hardware/heathkit_h89_complete_1.jpg title subtitle text image FLOPPY AND HARD-DRIVES Hard and Soft Sectors floppy-drives, along with hard-disk drive. /media/museum/hardware/heathkit_h89_drives_1.jpg title subtitle text image H77 FD UNIT 2 x 150 KB 5.25" drives unit with its dust cover. /media/museum/hardware/heathkit_h89_h77fdunit_1.jpg title subtitle text image HDOS MANUAL Floppy discs operating system manual /media/museum/software/heathkit_h89_hdosmanual_1.jpg 135 url date https://web.archive.org/web/20230331021329/http://www.old-computers.com/museum/computer.asp?c=135 2023-03-31

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