Programmable controller and methods of setting and displaying its internal information

摘要

A programmable controller has a programmable controller unit and a peripheral device which facilitates defining and managing set values of both the internal devices of the programmable controller and the upper and lower limit values by allowing the programmable controller unit and the peripheral device to store set values as reference values for judging the magnitudes of current values of information and updating these values under the control of a sequence program. Further, the programmable controller and peripheral device facilitate the consecutive display, real-time display, etc. of the contents of internal devices by displaying sequentially the contents of these internal devices at predetermined intervals under the control of a sequence program. Additionally this invention allows numerically represented character information stored in internal devices of a programmable controller to be displayed in the form of characters by a simple peripheral device. This display operates under the control of a sequence program and converts stored internal information into character information which indicates display shapes.