Abstract: A program development device provides a development environment of a user program executed by a control device. The program development device receives setting of an attribute related to reference from a program for each of one or more variables used in the user program including a first program and a second program having a calling relationship. The set attribute includes a first attribute referred to by any one of the first program and the second program and a second attribute referred to by both the first program and the second program. The program development device analyzes the user program and evaluates consistency based on the set attribute related to reference from the program for each of the one or more variables.

Abstract: A design assistance device includes: a design information storage section configured to store design information containing at least information of slave devices and information of a topology in a network system in accordance with a design created by a user; an actual configuration information generation section configured to generate actual configuration information containing at least the information of the slave devices and the information of the topology in the actual network system; a comparison section configured to compare the design information and the actual configuration information; and an output section configured to generate a comparison screen indicating the respective configurations of the designed network system and the actual network system along with their commonalities and differences and outputting the comparison screen to a display device.

Abstract: A design assistance device includes: a design information storage section configured to store design information containing at least information of slave devices and information of a topology in a network system in accordance with a design created by a user; an actual configuration information generation section configured to generate actual configuration information containing at least the information of the slave devices and the information of the topology in the actual network system; a comparison section configured to compare the design information and the actual configuration information; and an output section configured to generate a comparison screen indicating the respective configurations of the designed network system and the actual network system along with their commonalities and differences and outputting the comparison screen to a display device.

Abstract: A programmable controller system is formed by connecting a personal computer having an aid device program module installed to serve as an aid device for development of control program to a programmable controller having password protect function. A hardware key storing a specified password code is detachably attached to the personal computer. The aid device program module checks whether or not software module with a function of certifying a hardware key exists and if it is found to exist, it is linked as a part of the aid device program module and the function of certifying the hardware key is caused to operate.

Abstract: A programmable controller system is formed by connecting a personal computer having an aid device program module installed to serve as an aid device for development of control program to a programmable controller having password protect function. A hardware key storing a specified password code is detachably attached to the personal computer. The aid device program module checks whether or not software module with a function of certifying a hardware key exists and if it is found to exist, it is linked as a part of the aid device program module and the function of certifying the hardware key is caused to operate.

Abstract: A user program stored in a user program memory of a programmable controller includes a control program from which a description defining interlock conditions is excluded and an interlock program defining interlock conditions for the result of processing conforming to the control program and described separately from the control program. The control program is first read out of the user program memory, and operation processing is executed in accordance with the control program. The result of the operation is written into an I/O memory. Thereafter, the interlock program is read out of the user program memory, and operation processing conforming to the interlock program is executed. The result of the operation conforming to the interlock program is overwritten on the I/O memory.