This invention enables setting of a diagnosis algorithm of a safety device to be easily carried out. A slice I/O unit stores a plurality of diagnosis algorithms each corresponding to a different safety device in an ASIC, and stores specifying information for specifying a diagnosis algorithm to use of the plurality of diagnosis algorithms in a register of the ASIC. The slice I/O unit performs diagnosis of a connected safety device using the diagnosis algorithm specified by the specifying information stored in the register of the plurality of diagnosis algorithms. The diagnosis algorithm to use can be selected by selecting a number, and the like, which is preferable as a setting process at a setting tool device can be facilitated and a human error does not occur.