Control system, control device and control program

A control device, comprising:

• a processing unit that executes a user program;
• and
• a communication interface for communicating with one or a plurality of function units, wherein one or a plurality of communication units that relay data are disposed between the processing unit and the one or plurality of function units, wherein the control device comprises:
• a reflection means that, when a variable associated with any data held by the function units and indicating validity of the data is designated in the user program, reflects, as a value indicated by the variable, a result equivalent to a logical AND of state flags indicating that each of the communication units present on a transmission path from the function units holding designated data to the processing unit is sound.

A non-transitory computer-readable recording medium comprising a control program being a control program executed by a computer, the computer comprising a processing unit that executes a user program, and a communication interface for communicating with one or a plurality of function units, wherein one or a plurality of communication units that relay data are disposed between the processing unit and the one or plurality of function units,

• wherein the control program causes the computer to execute:
• a step of, when a variable associated with any data held by the function units and indicating validity of the data is designated in the user program, specifying a transmission path from the function units holding designated data to the processing unit and the communication units present on the specified transmission path;
• and
• a step of reflecting, as a value indicated by the variable, a result equivalent to a logical AND of state flags indicating that each of the specified communication units is sound.