--- title: BUILDING ITS OWN S-100 BUS BASED SYSTEM date: '1977-01-01' years: - '1977' topics: - Hardware params: when: month unknown 1977 image: /media/history/images/timeline_11-77_s100_1.jpg oc_id: 19 source: url: https://web.archive.org/web/20221215134357/http://www.old-computers.com/history/detail.asp?n=19 date: '2022-12-15' --- ![](/media/history/images/timeline_11-77_s100_1.jpg) In this end of year 1977, when a computer fanatic wished to build himself a powerful and evolutional computer, he'd only have pactically one choice: to purchase a S-100 Bus based system, assembled or in kit form.\ Several manufacturers were selling spare parts allowing to assemble progressively and at low cost a basic system. The first step consisted in acquiring a box with a power supply and a bus card.\ One had to choose then amongst several CPU cards available: Motorola 6800, MOS 6502, Intel 8080 and 8085 or Zilog Z80. The cards were provided assembled or in kit form. One had then to solder the components on the card.\ A third essential part, the RAM card. It was composed of 2 to 64 Kb of static or dynamic memory chip. At this stage, the computer was able to operate... providing that one could communicate with it! A teletype or video terminal plugged in the computer's serial port was then necessary.\ After a few days of operation, the user noticed that he would most probably need to buy a backup system to save his programs. For a few hundred $ more, he would rapidly buy a card punch or a cassette recorder with the additional interface card. Though his computer was working correctly and that our fanatic already spent approximately $1500, he's not yet acquainted that he'll have to spend approximately twice the price in the next months to purchase more memory, communication cards, one or two floppy drives, a printer, a modem... In 1977, when one would like to acquire a real computer, one had to be passionate, very handy... and rich! ![](/media/history/images/timeline_11-77_s100_2.jpg)