A Flexowriter interface for the Athena computer

Since the Athena computer was originally designed as a special purpose digital computer to provide guidance control for the Titan intercontinental ballistic missile, it lacks the input/output capabilities necessary for use as a general purpose computer. At the time this thesis was begun, the only method of programming the computer, other than manual insertion of data at the computer console, was the use of high-speed photoelectric punched-tape readers. However, no tapepunching equipment was available that would prepare tape compatible with the Athena word format and tape-reader circuitry. Other than visual observation of register contents at the console, the only data output device was a printer capable of printing the numeric contents of prescribed data registers. This paper describes the adaptation of Friden Flexo- writer typewriting machines as input/output devices for the Athena computer. Two such machines were available for this purpose. One machine was modified to serve as an off-line tapepunching device capable of punching and reproducing tape compatible with Athena word format and circuitry. The other machine is used as an on-line I/O device capable of direct machine language and alphanumeric loading of the computer's magnetic drum memory, as well as octal, decimal or alphanumeric printout of register contents.