3701113 is referenced by 45 patents and cites 11 patents.

A monitor for a programmed sequence of operations. A sequence controller responds to successive instructions. Some instructions correspond to elements of governing functions and test the status of independent variables to activate controllable devices, which correspond to dependent variables, when functions are satisfied. The monitor, operating in synchronism with the controller, generates a transition word each time the controller either (1) tests a sensor for an independent variable in the function or (2) prepares to alter a controllable device, if a comparison with the last condition of that sensor or device in a memory unit indicates a change has occurred or will occur. The monitor also updates this memory unit to the new condition. Each transition word identifies the changing element and describes the change. A data processing system stores each transition word in sequence for comparison with a reference list of transition sequences.

Title
Analyzer for sequencer controller
Application Number
05/171,542
Publication Number
3701113
Application Date
August 13, 1971
Publication Date
October 24, 1972
Inventor
Symmes David T
Steinberger Edward P
Ricketts Jr Alan W
Melvin Jr James A
Chace Donald E
Assignee
Digital Equipment Corporation
IPC
G05b 01/01
G05b 11/32
G06f 15/46
G05B 19/05
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