In a medical care apparatus (10), a host substrate (13) obtains comprehensive update data including pieces of update data of all attachable substrates, specifies a client substrate (11, 12, 14, 15, 16, 17) attached to the medical care apparatus (10), specifies the update data corresponding to the client substrate from the comprehensive update data, determines whether or not execution of update processing is necessary based on a program and the like of the client substrate and the update data, and sends at least the specified update data to the client substrate when determining that execution of the update processing is necessary. The client substrate executes the update processing based on the sent update data.
