Concurrent CP/M

Abstract

Most central processors spend their time doing very little. This is because many of the jobs being done by the computer, large or small, mainframe or micro, are protracted by the slowness of the data input and output. The input device is usually the keyboard, and even the speediest of typists cannot supply data at anything like the speed that it can be processed. Similarly, the speed of printers is far slower than the speed that the computer can hand over the data — hence the need for printer buffers. This is a problem that will be familiar to former users of mainframe and minicomputers; it was overcome by the use of a technique known as multi-programming. This enabled the computer to handle more than one program at a time. The result meant that, for example, while someone was editing a program on line the central processor could be getting on with some other task, say that of compiling a program in FORTRAN, in between the editing keystrokes.