Control system, control method, and non-transitory computer readable medium

A control method for a control system including a first control part and a second control part, the control method comprising:

• a step of acquiring a control program for a controller, the control program including a periodic-execution function module for invoking a non-periodic-execution function module;
• a step of causing the first control part to execute the control program;
• a step of, in a case where the periodic-execution function module is executed during execution of the control program, causing the first control part to reflect a value of an input variable for the periodic-execution function module in an argument for the non-periodic-execution function module and to output an execution start command for the non-periodic-execution function module to the second control part;
• a step of causing the second control part to start execution of the non-periodic-execution function module based on reception of the execution start command, and to output a return value for the non-periodic-execution function module to the first control part based on completion of the execution of the non-periodic-execution function module;
• and
• a step of causing the first control part to reflect the return value in an output variable for the periodic-execution function module based on reception of the return value from the second control part.

A non-transitory computer readable medium, storing a control program, which is a periodic-execution control program executed by a controller, the control program including a periodic-execution function module for invoking a non-periodic-execution function module, the controller including a first control part, and an external apparatus configured to be able to communicate with the controller or the controller including a second control part, the control program causing the first control part to execute:

• a step of executing the control program;
• a step of, in a case where the periodic-execution function module is executed during execution of the control program, reflecting a value of an input variable for the function module in an argument for the non-periodic-execution function module and outputting an execution start command for the non-periodic-execution function module to the second control part;
• and
• a step of, based on reception of an execution result of the non-periodic-execution function module from the second control part, reflecting the execution result in an output variable for the periodic-execution function module.