--- title: MITS ALTAIR 8800 categories: - Computers types: - Professional Computer origins: - U.S.A. years: - '1975' cpus: - Intel 8080A params: name: ALTAIR 8800 image: /media/museum/photos/mits_altair-8800_2.jpg company: /companies/mits company_name: MITS specs: - label: NAME value: ALTAIR 8800 - label: MANUFACTURER value: MITS - label: TYPE value: Professional Computer - label: ORIGIN value: U.S.A. - label: YEAR value: '1975' - label: KEYBOARD value: No keyboard, but switches on front panel. - label: CPU value: Intel 8080A (rarely 8080) - label: SPEED value: 2 MHz (each instruction takes 4 clock cycles) - label: RAM value: 256 bytes (you had to buy this memory board) - label: ROM value: None - label: TEXT MODES value: None (optional 64 x 12 card) - label: GRAPHIC MODES value: None - label: SIZE / WEIGHT value: Unknown - label: I/O PORTS value: Unknown - label: POWER SUPPLY value: Unknown - label: PRICE value: $595 tabs: - photos - adverts - hardware - emulators - links - docs - videos photos: - title: LARGE VIEW subtitle: '' text: '' image: /media/museum/photos/altair_8800_system_s1.jpg - title: 'FRONT PANEL #1' subtitle: '' text: '' image: /media/museum/photos/altair_8800b_fpanel_1.jpg - title: 'FRONT PANEL #2' subtitle: '' text: '' image: /media/museum/photos/altair_8800b_fpanel_2.jpg - title: TOP VIEW subtitle: '' text: '' image: /media/museum/photos/altair_8800b_top_1.jpg - title: INSIDE subtitle: '' text: Note that the back plane didn't receive all of its S-100 connectors. Only the CPU board is inserted. image: /media/museum/photos/altair_8800b_inside_1.jpg - title: ALTAIR PERIPHERALS subtitle: '' text: Various peripherals including a paper tape reader and 8'' floppy drive units image: /media/museum/photos/altair_8800_peripherals_1.jpg - title: THE TARBELL CASSETTE INTERFACE subtitle: '' text: This interface can be used with IMSAI or ALTAIR. It transfers from 187 to 540 bytes / second image: /media/museum/photos/tarbell_k7.jpg - title: BILL GATES subtitle: '' text: Bill Gate giving a demonstration of its first BASIC interpreter, written for the Altair 8800. image: /media/museum/photos/altair_8800_billgates_1.jpg - title: PROGRAM EXAMPLE subtitle: '' text: |- An example of assembly program user could enter using sense switches. Thanks to **Mark Thompson** image: /media/museum/photos/altair_8800_progsample_1.jpg - title: PAPER TAPES subtitle: '' text: |- Original Altair paper tape programs. This Assembler package consisted of a **Monitor**, an **Editor**, an **Assembler** and a **Debugger**. Thanks to **Mark Thompson** image: /media/museum/photos/altair_8800_papertapes_1.jpg adverts: - title: FIRST ADVERT subtitle: '' text: 'This painting was the first and the best known MITS Altair advert. It was created by Kim Behm who has since become a well-known artist. At the first beginning of the personal computers era, this advert seems to be saying: In a near future, everybody around the world will have access to a personal computer.' image: /media/museum/pubs/altair_8800_pub_1.jpg - title: 'ADVERT #2' subtitle: '' text: Thanks to **Mark Thompson** image: /media/museum/pubs/altair_8800_franklinad_1.jpg - title: POPULAR ELECTRONICS subtitle: '' text: Cover and extracts of a 6 page article in the January 1975 issue of Popular Electronics image: /media/museum/pubs/altair_8800_popularelectronics_1.jpg - title: SHOW BAG subtitle: '' text: '' image: /media/museum/pubs/altair_8800_bag_1.jpg - title: 1976 PRICE LIST subtitle: '' text: |- Notice that the 16K static RAM expansion is more expensive than the computer itself. Thanks to **Mark Thompson** image: /media/museum/pubs/altair_8800_pricelist_1.jpg - title: 1976 XMAS CATALOG subtitle: '' text: Thanks to **Mark Thompson** image: /media/museum/pubs/altair_8800_xmascatalog_1.jpg - title: 'MITS BROCHURE #1' subtitle: '' text: Thanks to **Mark Thompson** image: /media/museum/pubs/altair_8800_brochure_1.jpg - title: 'MITS BROCHURE #2' subtitle: '' text: '' image: /media/museum/pubs/altair_8800_salebrochure_s1.jpg - title: ALTAIR 'MOBILE' COURSE subtitle: '' text: Thanks to **Mark Thompson** image: /media/museum/pubs/altair_8800_course_1.jpg - title: COMPUTER NOTES subtitle: '' text: |- This fanzine - one of the first of the microcomputers era - was published by the Altair User Group Thanks to **Mark Thompson** image: /media/museum/pubs/altair_8800_compnotes_1.jpg - title: ALTAIR CONVENTION subtitle: '' text: |- The first Altair Convention was here announced in the Computer Notes magazine. Thanks to **Mark Thompson** image: /media/museum/pubs/altair_8800_compnotes_2.jpg - title: BIT SHOPPER subtitle: '' text: Spring 1978 issues of Byte Shopper image: /media/museum/pubs/altair_8800_bitshopper_1.jpg - title: EARLY ADVERT (SEPTEMBER 1975) subtitle: '' text: from Creative Computing magazine image: /media/museum/pubs/mits_altair_pub-creative-compuetug%20sept1975.jpg - title: EARLY ADVERT (SEPTEMBER 1975) subtitle: '' text: from Creative Computing magazine image: /media/museum/pubs/mits_altair_pub-creative-computing-sept1975_2.jpg - title: EARLY ADVERT (NOVEMBER 1975) subtitle: '' text: from Creative Computing magazine image: /media/museum/pubs/mits_altair_pub-creative-computing-nov1975.jpg hardware: - title: FLOPPY DISK SYSTEM subtitle: '' text: |- Advert (March 1977) said: "The North Star Micro-Disk System uses the Shugart minifloppy disc drive. The controller is an S-100 compatible PC board with on-board PROM for bootstrap load. It can control up to three drives. With the PROM bootstrap, we provide our powerful extended Basic (10 Kb) with sequential and random disk file accessing.\ Each 5.25'' diskette has 90k data byte capacity. Basic loads in less than 2 seconds. Micro-Disk system (kit) **$699**\ Micro-Disk system (Assembled) **$799**\ Additional drive **$425**\ Diskette **$4.5**" image: /media/museum/hardware/altair_8800_fd_1.jpg - title: CPU CARD subtitle: '' text: '' image: /media/museum/hardware/altair_8800_card_cpu_1.jpg - title: 1 KB STATIC RAM subtitle: '' text: '' image: /media/museum/hardware/altair_8800_card_1kstatic_1.jpg - title: 4 KB DYNAMIC RAM subtitle: '' text: '' image: /media/museum/hardware/altair_8800_card_4kdram_1.jpg - title: SERIAL I/O CARD subtitle: '' text: '' image: /media/museum/hardware/altair_8800_card_serialio_1.jpg - title: TEST CARD subtitle: '' text: Tis card was used to test each contact of a S-100 connector image: /media/museum/hardware/altair_8800_testconnectorboard.jpg - title: US ADVERT (1977) subtitle: '' text: You could use these joysticks with the Altair or any S100 bus system. They connect to the Cromenco D+7/A I/O board and were meant to play the games available for the Cromenco TV Dazzler, the first video card for personal computer. image: /media/museum/hardware/cromenco-joysticks_pub_1-1977.jpg emulators: - title: SIMH url: http://simh.trailing-edge.com/ platform: Windows text: Windows emulator for a lot of mini computers. Sources are available so you can compile them for your own platform. - title: Altair and IMSAI Emulators url: http://www.threedee.com/jcm/emu8080/index.html platform: Other platform text: A list of Altair / IMSAI emulators links: - title: Altair 8800 brochures url: http://altair.ftldesign.com/ text: 1974 - 1976 Altair 8800 Brochures and Price Lists - title: 'Computers : from the past to present' url: http://www.eingang.org/Lecture/altair.html text: Altair page - title: The Virtual Altair Museum url: http://www.virtualaltair.com/ text: Infos about MITS/Pertec Altair 8800/680b/MITS 300/Attache systems docs: - title: OPERATOR'S MANUAL url: http://www.1000bit.net/support/manuali/manuali.asp cover: /media/museum/docs/couvs/mits_altair8800_operator-manual.jpg text: |- [**OPERATOR'S MANUAL**](http://www.1000bit.net/support/manuali/manuali.asp)written by MITS  compiled/archived by Robert Krten\  type of document : PDF\  size : 5,5 MB\  source : [www.1000bit.net](http://www.1000bit.net) - title: ASSEMBLY MANUAL url: http://www.1000bit.net/support/manuali/manuali.asp cover: /media/museum/docs/couvs/mits_altair8800_assembly-manual.jpg text: |- [**ASSEMBLY MANUAL**](http://www.1000bit.net/support/manuali/manuali.asp)written by MITS  compiled/archived by Robert Krten\  type of document : PDF\  size : 7 MB\  source : [www.1000bit.net](http://www.1000bit.net) - title: THEORY OF OPERATIONS - MANUAL & SCHEMATICS url: http://www.1000bit.net/support/manuali/manuali.asp cover: /media/museum/docs/couvs/mits_altair8800_theory-of-operation.jpg text: |- [**THEORY OF OPERATIONS - MANUAL & SCHEMATICS**](http://www.1000bit.net/support/manuali/manuali.asp)written by MITS  compiled/archived by Robert Krten\  type of document : PDF\  size : 387 KB\  source : [www.1000bit.net](http://www.1000bit.net) - title: VARIOUS SCHEMATICS url: http://www.1000bit.net/support/manuali/manuali.asp cover: /media/museum/docs/couvs/mits_altair8800_schematics.jpg text: |- [**VARIOUS SCHEMATICS**](http://www.1000bit.net/support/manuali/manuali.asp)written by MITS  compiled/archived by Robert Krten\  type of document : PDF\  size : 936 KB\  source : [www.1000bit.net](http://www.1000bit.net) videos: - title: MITS Altair 8800 demonstration url: https://www.youtube.com/watch?v=vAhp_LzvSWk text: 'Length: 8 min 45 s' - title: How the Altair 8800 started the PC revolution url: https://www.youtube.com/watch?v=WVwfDA4watU text: 'Length: 7 min 40 s' - title: ALTAIR 8800 -The Computer that started Microsoft url: https://www.youtube.com/watch?v=vD4xHCW9YCQ text: 'Length: 3 min 14 s' comments: - author: Jay Lucas (United States) date: Thursday 28th November 2019 text: Hi All, I''m Jay Lucas, and I have been "into" microcomputers for a long time. My wife is cleaning out the basement, and if anyone wants my old Altair 8800, or its 8" Floppy drive, or one of three Apple Newtons, or any of my 4 Macintosh original computers, let me know. jaylucas@me.com or phone at 703.347.2000 (text preferred). I''m in Alexandria, VA. - author: David Payne (Melbourne, Australia) date: Monday 10th February 2014 text: |- "Forbidden Planet" was set on Altair 4 which would usually mean the 4th planet orbiting Altair counting outwards. Likewise Earth is sometimes referred to as Sol 3.\ I think the Star Trek planet was another number presumably orbitting Altair. Given the size of the brightness at the end of "Forbidden Planet" it would have to be much further out or in a different fictional universe. - author: David Payne (Melbourne, Australia) date: Monday 10th February 2014 text: |- I think after the first 30 or so bytes the loading process would get tiresome, particularly if you had nearly finished $ someone kicked the power plug as happened at Steve Dompier''s famous demo. http://en.wikipedia.org/wiki/Daisy_Bell - author: James Parsons (U.S.A.) date: Wednesday 6th November 2013 text: Ahh it would be fun to flip the data and address bus''s on and off :D - author: James Parsons (U.S.A.) date: Wednesday 6th November 2013 text: Ahh it would be fun to flip the data and address bus''s on and off :D - author: Dave Brandt (US) date: Monday 11th April 2011 text: Ha! The name Altair came from the great sci-fi movie of the 1950''s, ''''Forbidden Planet", starring Leslie Nielson. Evidently Mr. Roddenberry was a Forbidden Planet fan as well! - author: Pete Bickerdike (USA) date: Monday 5th January 2009 text: |- I had an early Altair bought as a kit from Dick Heiser''s computer store in Los Angeles, had it in my Winnebago motorhome with a LS 7700A terminal. On a trip around the US in the motorhome, I bought a second dynamic 4K card from Bruce Seals (later to become Seals Electronics - another story) at his Knoxville, TN Byte Shop. The card didn''t work, stopped at MITS in NM on the way back to California, they showed me their repair facility and said that I could leave the card to be repaired if I wanted, said "no thanks" after seeing the 50 or 60 card pile awaiting repair. I fixed the card myself, finding the refresh timimg was off, they used one-shots to time the refresh, with poor timing components. It took a dual trace scope and careful comparison against my working 4K card. I used the Altair for many years, toggling in the bootstrap loader for the basic loaded from cassete tape. - author: Paul Stevens (South Africa) date: Tuesday 4th June 2002 text: In 1975 When Bill Gates and Paul Allen Got their lates copy of Popular Electronics With The Story about the Altair 8800 they realised that this was what they were waiting for, they started a new company soon after called Micro-Soft - author: Jay S. Curtis (NY) date: Tuesday 21st May 2002 text: I built the IMSAI 8080(A) in '76. It took 4 months and cost $625 at the time. I sold it in 1980 after upgrading to text video (TV) and 1K ram for $800 - author: Martin (Sweden) date: Monday 25th March 2002 text: |- Hello all!\ I wonde if there is a homepage where\ you can find the manuals for the Altair\ cause i got the emulator but i dont know\ how to use it (= related: - /museum/imsai-8080 oc_id: 62 source: url: https://web.archive.org/web/20230413211213/http://www.old-computers.com/museum/computer.asp?c=62 date: '2023-04-13' --- This computer was one of the first "home" computers ever made, it was sold as a kit, but for additional money, you could buy one fully assembled. It had no keyboard, the "program" had to be entered with the switches located on the front panel of the "computer", and as it didn't have video output (yet), the result was displayed via LEDs. Another computer which had almost the same characteristics was launched by IMSAI and was called [IMSAI 8080](/museum/imsai-8080/) (see both in the "Emulators" section). The ALTAIR 8800 had one input port, also called the "Sense Switches" (I/O address 255) which was the left hand 8 address switches. Address 255 was also used on the IMSAI. The IMSAI front panel differed from the Altair in that you could also output to port 255 to a displayed LED buffer above the sense switches - a feature the Altair did not have (it only had input). The Altair sense switch were used during boot into Altair DOS to specify the terminal port to the DOS. MITS made several peripherals and cards for this computer, namely, a video card, a serial card to connect a terminal, a RAM expansion card and a 8" floppy drive that used hard sectored floppies and stored 300 KB. Several models were launched, they had the same characteristics except the CPU (8080 and later 8080A). Believe it or not, the name "Altair" comes from Star Trek! The young daughter of the 'Popular Electronics' magazine editor gave it the name of the destination planet of the Enterprise from the episode she was watching.