Control Program for Micros

Disk operating systems roots

1960 DEC builds OS/8 for PDP-8
- Has PDP-10 feel, but with very limited memory

DEC also builds RT-11 for PDP-11's

Gary Kildall - instructor at Naval Post Graduate School in Monterey, CA

- 1974 builds PL/M language for Intellec 4 and then Intellec 8
- Intellec is a development system for Intel Microprocessors

- Also builds CP/M
- Disk operating system
- borrowed some commands from DEC
- identified drives by letter
- xxxxxx.yyy file names
- DIR command

1976 CP/M announced in
Dr. Dobbs Journal of Computer Calisthenics and Orthodontia

1977 CP/M for IMSAI
- rewritten so that only a small part has to be redone for each new machine or disk drive
- the specialized code is called Basic Input/Output System (BIOS)
- and it becomes a system software standard

Notes

Bibliography

Martin Campbell-Kelly and William Aspray. Computer: A History of the Information Machine (Basic Books, 1996).

Paul E. Ceruzzi, A History of Modern Computing, 2nd ed. (Cambridge, MA: MIT Press, 2003).