Who remembers the Sol-20? Us neither, but it was an important milestone on the path to where by we, and our computers, are today. Without the Sol-20 the household personal computer environment would be incredibly diverse. This important stage in property pc record is an superb option, then, for a retro personal computer replica undertaking these kinds of as that carried out by Michael Gardi (and highlighted by Hackaday) employing a Raspberry Pi in area of the Intel 8080 at the primary computer’s coronary heart.
The 1st fully assembled microcomputer with both of those a constructed-in keyboard and a Television output, the Sol-20 had the misfortune to be released in 1976, a yr ahead of Apple, Commodore and Tandy came and stomped all about the current market with the Apple II, Pet and TRS-80. Originally offered in a few versions – a motherboard kit the Sol-10 added a scenario, keyboard and energy offer, but came with no enlargement slots and the Sol-20 beefed up that electric power supply and included five S-100 bus slots (the Sol-20 would be by significantly the most well-known design). The computer system stayed in production right up until 1979 and would offer close to 12,000 units, generating them very exceptional today. For distinction, complete Apple II gross sales would strike around six million, together with a million in 1983 by itself.
For the 2021 edition, obtaining an authentic-wanting situation was a precedence. The unique blue primary was manufactured of sheet steel with wood sides, but Gardi reached for his 3D printer rather than his slicing torch to make the create much more available to other folks. The sides are created from walnut, a content slightly befitting the aesthetic of the time.
Gardi also manufactured a matching display for the Sol-20, yet again 3D printed and embellished with walnut, it utilises a 4:3 Liquid crystal display panel and connects to the Pi via an HDMI cable.
The keyboard is a reproduction of the first in structure, but sits on modern-day Cherry MX switches. The board will come as a kit from osiweb.org. The brains of the operation is a Raspberry Pi 4 running an 8080 emulator prepared in Python and forked from one accessible on GitHub. The digital CPU has 64kb of memory (most devices transported with 8 or 16kb) and supports storage on digital cassette tapes. There is certainly a large amount – and we suggest a whole lot – a lot more element on Gardi’s Hackaday.io task web page, such as his use of an Arduino as a keyboard interface, the development of an RS232 port, and his accomplishment ‘drawing’ the Sol-20 symbol on a rectangle of acrylic employing his 3D printer.