A Quick Tour of History​

​

The MITS Altair 8800 was the very first ready-to-order microcomputer. In its original shape, it had no keyboard or screen, let alone a diskdrive. One was supposed to key in software byte for byte through the front panel, and read out the results from memory bytes through LEDs. There is a great emulator of the original bare-bones Altair.

​

The ad to the left is from February, 1977 and shows the whole Altair product range of MITS, at a time when peripherals suchs as a disk drive and paper tape reader were already introduced. MITS had a poor quality reputation, and that - in combination with the machine having an open expansion bus - sparked off the S-100 computer industry.

​

Soon, serial terminals were attached and disk drive units became available. Gary Kildall, founder of Digital Research, wrote CP/M as a standard disk operating system. Version 1.4 was the first public version, and was tied closely to the use of 8" disks. Version 2.2 was the next version for general release. This version made significant improvements, most notably, the support of 5.25" disks and increased hardware independence. A version 3 became available much later, after CP/M had already peaked in its popularity. MP/M was a multi-user version of CP/M.

​

The S-100 card cage computers

​

Soon after the Altair, a whole range of S-100 computer vendors sprang up. Where Altair was noted for its cheap but flaky hardware, Cromemco was at the high quality end of the spectrum. Cromemco, more than any other company, commercialised the microcomputer in its first years. Their machines were typical of the early CP/M machines: large metal boxes with a motherboard, which only held a row of connectors. The computer was built up from a processor card, floppy disk card, memory card and interface card - all of which were plugged in to the motherboard.

​

Many premier computer names of this era started as DIY part vendors. To the left is an early advert from Godbout, who became known as the king of the S-100 system builders.

​

The rise of the all-in-one designs​

The S-100 bus, although very expandable, was a bulky way of building computers. At the end of the 70s, all-in-one type computers become more prevalent. With keyboard and screen built in and a small single motherboard rather than a card cage with separate processor, disk and memory cards, these machines were way cheaper to build - and probably, a lot more reliable in most cases.

The Intertec Superbrain was one of these early all-in-one designs. To this day, it is one of the fastest computers in daily use. Booting took seconds, loading the WordStar wordprocesor from disk only a few more. These machines show how effective and efficient CP/M could really be. 'Luggable' CP/M machines came fairly quickly afterwards, most notably the Osborne 1, followed by the great KayPro machines.

​

'Modern' CP/M incarnations​

​

At the end of its life span, in 1982-1985, CP/M-compatible hardware had become very cheap to manufacture. CP/M computers had always been at the upper end of the microcomputer market, but with the arrival of machines like the Bondwell 12, CP/M systems now became very affordable. Even later, Amstrad in the UK would offer CP/M as an option on its cheap home computers - as Commodore did on its 128.

Not all later CP/M computers were of the cheap and cheerful kind. Epson produced the Epson PX-8 in 1983, the first laptop with normal functionality: an LCD screen, a RAM disk and microcassette tape drive for storage, and built-in P/M and WordStar on ROM capsules. The PX-8 stands out as one of the most impressive engineering feats ever in microcomputer history.