General principles of computer systems.

Abstract

Computers are machines which accept, process, and display information. Depending upon certain characteristics they are categorized as being either analogue or digital. The central processing unit for a digital computer comprises a memory section, a control section, and an arithmetic and logical unit. Extremely fast internal speeds and the many‐place accuracy of arithmetic calculations are trademarks, but the real power of a digital computer lies in its ability to take advantage of the "stored‐program concept." The fact that an analogue computer is particularly adept at solving ordinary differential equations has made it an efficient simulator of many physiological phenomena. Compared to its digital cousin the cast of this computer is low and it is a relatively simple machine from an engineering point of view. These and other factars are responsible for its popularity as a special‐purpose computer in a laboratory. It has become obvious that the virtues of both of these types of computers are important in the biomedical sciences. This need is responsible for a third type of computer called the hybrid computer. An interface is used between the analogue computer and the digital computer as a controlling facility in the hybrid system. In a true hybrid environment, either of the two types of computers may control the other at a given time.