JPS6457301A - Process controller - Google Patents

Abstract

PURPOSE:To interpolate process control without generating a gap by storing an executing processing instructing step at the time of stopping the operation of a master controller and a process control result in the stop period in a controller device, and at the time of recovering the operation, sending these stored contents. CONSTITUTION:A process controller is provided with a master controller 101 and a controller device 108, the controller 101 is constituted of storage parts 102-104 for a processing instruction, etc. an operation control part 105 and a communication controller 106 and the device 108 is constituted of a communication controller 109, a master controller state deciding part 110, an operation control part 111, a process signal I/O part 112, and storage parts 113-115 for a processing instruction, etc. Said deciding part 110 decides whether the controller 101 is in operating or not and catches the start or end timing of backup processing based on the device 108 synchronously with the operation stop or recovery timing of the controller 101. At the time of deciding non-operation, the processing instruction step, etc., in executing is stored, and at the time of deciding its recovery, backup processing is executed.