SEQUENCE CONTROLLER, MAINTENANCE METHOD FOR MAINTENANCE AREA IN THE SAME DEVICE, AND RECORDING MEDIUM FOR STORING COMPUTER PROGRAM FOR EXECUTING THE SAME METHOD

PROBLEM TO BE SOLVED: To realize the maintenance area of data to be used by a sequence controller in an inexpensive form in which any maintenance is not necessary. SOLUTION: This device is constituted of a holding area 2A formed in a data memory 2 for holing data at the time of the end of sequence control, an auxiliary storing means 3 constituted of a hard disk for holding the data in the holding area 2A, and a run time engine 1 for writing the data in the holding area 2A in the auxiliary storage means 3 at the time of the end of the sequence control, and for reading the data written in the auxiliary storage means 3 and writing the data in the memory of the holding area 2A at the time of the start of the sequence control. It is not necessary to use any non- volatile memory for the data memory 2 constructing the holding area 2A, and it is possible to construct an inexpensive system.