A slave device, connected to a controller as a master device through a network, and having a communication port connected to a device, the slave device comprising: a mode setting part, configured to set the device connected to the communication port to communicate with the slave device in a first mode or a second mode, the first mode being a mode of only receiving 1-bit data and the second mode being a mode of receiving more than 1 bit of data; a storage part, configured to store configuration information comprising recognition information of the device predetermined to be connected to the communication port; a comparing part, configured to execute comparison processing when the mode setting part sets the second mode, and executing no comparison processing when the mode setting part sets the first mode, wherein the comparison processing is for determining a consistency of a recognition information of the device included in the data received from the device being larger than 1 bit and the recognition information included in the configuration information stored by the storage part; and a transmitting part, configured to transmit the data received from the device communicating in the first mode to the network in a data format when the mode setting part sets the first mode, wherein the data format is used for transmitting the data received from the device to the network when the mode setting part sets the second mode, wherein the data format comprises: a first position for storing only 1-bit data at which the 1-bit data received from the device is stored regardless of whether the comparison processing is executed; and a second position at which data other than the data stored in the first position among the data received from the device is stored when the comparison processing is executed, and 0 is stored when the comparison processing is not executed. a mode setting part, configured to set the device connected to the communication port to communicate with the slave device in a first mode or a second mode, the first mode being a mode of only receiving 1-bit data and the second mode being a mode of receiving more than 1 bit of data; a storage part, configured to store configuration information comprising recognition information of the device predetermined to be connected to the communication port; a comparing part, configured to execute comparison processing when the mode setting part sets the second mode, and executing no comparison processing when the mode setting part sets the first mode, wherein the comparison processing is for determining a consistency of a recognition information of the device included in the data received from the device being larger than 1 bit and the recognition information included in the configuration information stored by the storage part; and a transmitting part, configured to transmit the data received from the device communicating in the first mode to the network in a data format when the mode setting part sets the first mode, wherein the data format is used for transmitting the data received from the device to the network when the mode setting part sets the second mode, wherein the data format comprises: a first position for storing only 1-bit data at which the 1-bit data received from the device is stored regardless of whether the comparison processing is executed; and a second position at which data other than the data stored in the first position among the data received from the device is stored when the comparison processing is executed, and 0 is stored when the comparison processing is not executed. a first position for storing only 1-bit data at which the 1-bit data received from the device is stored regardless of whether the comparison processing is executed; and a second position at which data other than the data stored in the first position among the data received from the device is stored when the comparison processing is executed, and 0 is stored when the comparison processing is not executed.