website/content/museum/heathkit-h8.md

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

title	categories	types	origins	years	cpus	params
HEATHKIT H8	Computers	Professional Computer	U.S.A.	1977	Intel 8080 A	name image company company_name specs tabs photos adverts hardware emulators links docs comments oc_id source H8 /media/museum/photos/heathkit_h8_1.jpg /companies/heathkit HEATHKIT label value NAME H8 label value MANUFACTURER Heathkit label value TYPE Professional Computer label value ORIGIN U.S.A. label value YEAR September 1977 label value END OF PRODUCTION Unknown label value BUILT IN LANGUAGE Octal editor label value KEYBOARD 16--key Octal label value CPU Intel 8080 A label value SPEED 2.048 MHz label value RAM 256 bytes (upgradable with memory boards) label value ROM 1 KB in basic version label value TEXT MODES N/A - Small display on the front panel displays the registers content. label value SOUND Built-in speaker label value SIZE / WEIGHT Unknown label value I/O PORTS Serial IO (H8-4) and Cassette Interface (H8-5) label value BUILT IN MEDIA Optional ECP-3801 Cassette Recorder / Player label value OS HDOS, CP/M with extended system label value POWER SUPPLY Built-in power supply unit label value PRICE From $499 photos adverts hardware emulators links docs title subtitle text image COMPLETE SYSTEM Complete system with H9 terminal and paper tape reader / punch expansion /media/museum/photos/heathkit_h8_complete-system_2.jpg title subtitle text image COMPLETE SYSTEM #2 Here is a Heathkit H8 computer with a terminal and a floppy-drive. /media/museum/photos/heathkit_h8_2.jpg title subtitle text image INSIDE We can see here the different boards of the computer. The second board from bottom is a 64k RAM expansion board. /media/museum/photos/heathkit_h8_inside.jpg title subtitle text image FRENCH ADVERT (1979) /media/museum/pubs/heathkit_h8_pub_2.jpg title subtitle text image U.S. ADVERT (1980) At the time of this advert (September 1980), Heathkit introduced a music synthetiser board, a speech lab, a color graphic board, a color monitor and Microsoft BASIC and FORTRAN languages. /media/museum/pubs/heathkit_h8_pub_1.jpg title subtitle text image H9 TERMINAL This was the first and official terminal for the H8 computer. It is nicely shaped. /media/museum/hardware/heathkit_h9_2.jpg title subtitle text image H17 DISK DRIVE UNIT The H17 Disk Drive and HDOS (Heath Disk Operating System) were released in late 1978. The unit featured one or two hard sectored 5.25" 102.4 KB disk drives, and was delivered with a disk controller card for the H8. /media/museum/hardware/heathkit_h8_h17fdunit_1.jpg title subtitle text image 8'' DISK-DRIVES /media/museum/hardware/heathkit_h8_diskdrives_1.jpg title subtitle text image PAPER TAPE READER / PUNCH This mass storage peripheral was the ancestor of the tape recorder. It used paper tapes and had independant punch and reader mechanisms allowing tape duplication. It red up to 50 characters per second and punched up to 10 characters per second. Price: $350 in kit form. /media/museum/hardware/heathkit_h8_puncher_1.jpg title url platform text Virtual H8 Project http://davidwallace2000.home.comcast.net/h8/The_Heathkit_H8_Digital_Computer.htm Windows Nice designed emulator title url platform text Project 8080 http://davidwallace2000.home.comcast.net/h8/project8080_archive/heath8080a_intro.htm Apple A H8 emulator for the Mac title url text Daves Old Computers - Heathkit H8 http://parse.com/~ddunfield/museum/h8/index.htm Interesting page with nice pictures and many docs to download title url text Techno-Paleontology : Compusaurus Heathkitus http://davidwallace2000.home.comcast.net/ Infos, technical data and home of the Virtual H8 Project. title url cover text HEATHKIT H8 - OPERATION MANUAL http://www.classiccmp.org/dunfield/heath/index.htm /media/museum/docs/couvs/heathkit_h8_operation-manual.jpg [**HEATHKIT H8 - OPERATION MANUAL**](http://www.classiccmp.org/dunfield/heath/index.htm)written by Heath Company  compiled/archived by Dave Dunfield\  type of document : PDF\  source : [Daves Old Computers](http://www.classiccmp.org/dunfield/heath/index.htm) title url cover text HEATHKIT H8 - ASSEMBLY MANUAL http://www.classiccmp.org/dunfield/heath/index.htm /media/museum/docs/couvs/heathkit_h8_assembly-manual.jpg [**HEATHKIT H8 - ASSEMBLY MANUAL**](http://www.classiccmp.org/dunfield/heath/index.htm)written by Heath Company  compiled/archived by Dave Dunfield\  type of document : PDF\  source : [Daves Old Computers](http://www.classiccmp.org/dunfield/heath/index.htm) title url cover text HEATHKIT H8 - 4K STATIC MEMORY BOARD http://www.classiccmp.org/dunfield/heath/index.htm /media/museum/docs/couvs/heathkit_h8_4k-static-memory-board.jpg [**HEATHKIT H8 - 4K STATIC MEMORY BOARD**](http://www.classiccmp.org/dunfield/heath/index.htm)written by Heath Company  compiled/archived by Dave Dunfield\  type of document : PDF\  source : [Daves Old Computers](http://www.classiccmp.org/dunfield/heath/index.htm) title url cover text HEATHKIT H8 - SERIAL I/O AND CASSETTE INTERFACE CARD http://www.classiccmp.org/dunfield/heath/index.htm /media/museum/docs/couvs/heathkit_h8_serial-and-cassette-interface.jpg [**HEATHKIT H8 - SERIAL I/O AND CASSETTE INTERFACE CARD**](http://www.classiccmp.org/dunfield/heath/index.htm)written by Heath Company  compiled/archived by Dave Dunfield\  type of document : PDF\  source : [Daves Old Computers](http://www.classiccmp.org/dunfield/heath/index.htm) author date text David Hansen (IOWA USA) Saturday 24th February 2018 I found an h8 and h9 monitor. The h9 works the h8 needs work. I have all manuals and schmatic and documents related to this machine. also correspondence between original owner and heath kit company. email me if interested I can send pictures and more info. author date text Dave Johnson (United States) Saturday 21st January 2017 The H8 with the H9 monitor was my first computer. I built in in my dad''s basement just before I was transferred to Germany. I was 32 years old and had dabbled in programming for years. (Took BASIC class at BYU in 1964). The H8 was built like a tank! the 32K static RAM ran hotter than the fires of Hades. I think the all steel construction was part of the heat sink design. I loved that computer. I went on to become an IT manager for the federal government and it all started with my beloved H8! I wish I still had it! author date text Paul Domholdt (Los Angleles, CA) Saturday 10th December 2005 The boards I had are now gone. A couple of folks did contact me and bought up what I had. Still have fond memories of the years I had my H8! Good lucking finding parts/boards for those looking. author date text Paul Domholdt (Los Angeles, CA) Friday 31st May 2002 This was my first computer, built it back in the summer of 1979. Was a great computer, learned a lot from it. I've still got some old boards for the H8 if anybody has any interest in them contact me via email. Paul 134 url date https://web.archive.org/web/20230323144800/http://www.old-computers.com/museum/computer.asp?c=134 2023-03-23

This early computer was to be used with a terminal for better control.

A lots of expansion boards were available for this computer. Memory boards were available in 4K, 8K, and 16K (note: 4k memory board was 8k half populated.)

The H8 was sold with software: Benton Harbor BASIC, the HASL-8 2 pass assembler, TED-8 Line oriented text editor and BUG-8 terminal console debugger.

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Further information from John H. Swalby:
Built, used, developed on H8 from 77-84. no longer have any hardware, manuals, etc. just some old photos.
1) the keypad is Octal, as is the display. in fact, the 8080 is basically an octal oriented machine. the instructions are mostly based on 3 bit source and destination fields. Heathkit's early software offerings were all octal. HASL & Bug-8. they used a peculiar bastardized version called "split octal" where each word is represented by 2 octal bytes. so address range looked like 000 000 to 377 377 (0x0000 to 0xFFFF) as opposed to 000000 to 177777.
2) As the product matured, Heath offered a CPU replacement card based on the Z80. This ran CP/M instead of HDOS. Also most of Gates' early stuff, ASM-80, BASIC-80, FORTRAN-80, etc, also UCSD-Pascal p-system was offered.
3) Chassis had large unregulated power supply. Up to 2 regulators were mounted on an aluminium bracket on each card to spread out the heat dissipation. There was no motherboard per se. There was an 88 pin 'backplane' along the right side of the box. The cards were mounted at an angle roughly parallel to the front panel. This was to optimise convection cooling. There were NO FANS. There was a small speaker to beep and add key-clicks for the keypad.
4) Add on cards included: 2-port serial I/O for terminal and casette recorder interface; 4-port serial I/O; H17 floppy disk interface; 2-channel D/A card with 4 part music synthesis software; parallel interface card (possibly for high speed (300baud) papertape reader/punch).
5) The H17 floppy drive was a separate box connected by a ribbon cable. It supported up to 2 - 5.25" full height Wangco drives. Disks were 10 sector - hard sectored floppies. This means there were 11 index holes around the hub. 1 for start of track, and one for each sector! These were VERY expensive. $65.00cdn for a box of 5. Under HDOS they held 104K, under CP/M 80K, formatted. Usually O/S, editor, compilers, utilities were on the first disk; while sources, objects, lists, and user executables were kept on the second.

Jacques Trepanier remembers:
My father bought one in june of 1976 and we were members of the HUG (Heathkit User Group) in Montreal, Canada in 1977.
We ran Benton Harbor basic (from heathkit) and I programmed the 8080 directly using the 16 key keypad. We had an audio tape cassette and a H9 monitor converted to display 24 X 80 caracters (originally it was 12 X 80.
The computer built in language was not hexadecimal, it was split octal.
Also, the computer came with 256 bytes of RAM. You had to buy memory boards, either 4k or 8k. The 4k board was a half populated 8k board. In 76-77 a 8k RAM board was worth $1000 canadian in Montreal.
The H8 had a built-in speaker and it biped when you turned it on. Some people developped music programs in machine language and you had to modify the speager circuitery to play music. It was an RC (Resistor Capacitor) filter if I remember correctly . Our computer play New York new York and The Sting among other popular songs. We copied that music from US magazines.