On the efficient use of a minicomputer with limited I/O

Abstract

We have recently received a Varian 520/i minicomputer to be used mainly for teaching purposes. Since our only I/O device is a standard teletype (equipped with a paper tape read/punch), we immediately faced the problem of software development. The existing system programs for that purpose, namely the assemblers, loaders and editor are very impractical to use with a teletype. A typical step in the debugging process involves: (1) loading the assembler, (2) assembling the program, (3) loading the program (normally overlaying the assembler or part of it), (4) executing the program and deciding on necessary changes, (5) loading the editor, and (6) editing the changes into the source paper tape.