Abstract: A delay lock loop has a fixed delay element, means for detecting the edge transitions of pulses, analog or digital feedback means related to the timing differences between the edge transitions of a pair of pulses and a variable delay means responsive to the feedback means for adjusting the timing differences between a pair of pulses in response to the feedback signals. In the analog embodiment, the feedback may be a voltage related feedback with a varying voltage controlling a voltage responsive variable delay means. In the digital embodiment, the feedback means may use a counter responsive to signals from an edge detecting flip-flop and the counter may control a programmable delay means.

Abstract: A monitor and control apparatus according to the present disclosure includes a configuration and environment monitor (CEM) connected to a plurality of remote station monitors of a computer system for executing commands at the remote stations and for monitoring abnormal conditions thereat. The remote monitors each include a Johnson counter responsive to clock signals from the CEM to sequentially step through its output positions. Address means is selectively connected to first output positions of the Johnson counter to provide a unique address for each remote monitor. Monitor means receives monitor condition signals and is arranged with a transmitter to transmit a signal to the CEM upon sensing a fault. The CEM then sequences the Johnson counters to cause the address and fault identification data in the operated monitor to be transmitted to the CEM.