6. Hardware Monitors
Saul Rosen · Society for Industrial and Applied Mathematics eBooks · 1976
6.1. Introduction. From the time of the very earliest computers, panel lights were used to indicate when the various control flip-flops in the system were set, and when the various system components were being used. The engineers who design and build and maintain electronic computing equipment have always had to have the ability to attach oscilloscopes and other instruments to test points in the system while the system is running, without interfering with the running system.