PDP-7

computer A minicomputer sold by DEC in 1964. It had a

memory cycle time of 1.75 microseconds and add time of 4

microseconds. I/O included a keyboard, printer, paper-tape

and dual transport DECtape drives (type 555).

DEC provided an "advanced" Fortran II compiler, a Symbolic

Assembler, Editor, DDT Debugging System, Maintenance

routines and a library of arithmetic, utility and programming

aids developed on the program-compatible PDP-4.

[DEC sales brochure].

The PDP-7 was considered reliable enough (when properly

programmed) to be used for control of nuclear reactors and

such.

Around 1970 Ken Thompson built the operating system that

became Unix on a scavenged PDP-7 so he could play a

descendant of the SPACEWAR game.

(1995-03-10)