Abstract: A method of acquiring status information of I/O units connected to a numerical controller capable of transmitting status information indicative of particulars of an abnormality occurred in any of the I/O units with less influence on an amount of transmittable information of input/output data. When an abnormality has occurred in the I/O unit, the I/O unit transmits an output signal with a status abnormality notifying bit set to a programmable controller (PC) in the numerical controller. The PC stores information indicative of I/O units in which the status abnormality has occurred as status-abnormality acquiring I/O unit information, in a storage device of the PC. The PC requests the status information to the I/O unit in which the abnormality has occurred according to the status-abnormality acquiring I/O unit information. In response to the request, the I/O unit transmits the status information to the PC.

Abstract: A numerical controller in which group IDs are automatically allocated to I/O units so that the group IDs and addresses can be set automatically even when a system configuration is changed in response to detection of a configuration error. When a power of the numerical controller is turned on, group IDs are successively allocated to I/O units with distance from the numerical controller, and types of the I/O units are stored. Initial values of the group IDs allocated when the power is turned on for the first time after a system of the numerical controller is constructed, and addresses for the allocated group IDs are stored. An alarm is issued if the types and number of units for the group IDs automatically allocated for the second or later time of starting the numerical controller are different from the initial values.

Abstract: Each of the host transmitting/receiving blocks of a plurality of I/O units connected to a CNC reads the destination specification data and a diagnostic result bit each time the host transmitting/receiving block receives a signal packet from the CNC. When the diagnostic result bit indicates the execution of a diagnosis, the signal packet contains diagnostic DO data, and the relevant DO signal output terminal is short-circuited to the relevant DI signal input terminal to form a diagnostic loop. The diagnostic packet signal passes through the diagnostic loop, the external signal transmitting/receiving block, and the host transmitting/receiving block and returns to the CNC through the host transmitting/receiving block of an adjacent I/O unit closer to the CNC. The CNC analyzes the packet signal to determine whether each of the I/O units is operating normally or not.

Abstract: A GPS receiver is provided within a controller. When the customer orders the option software, the ID information identifying the controller and the positional information acquired by the GPS receiver are transmitted to a management apparatus on the controller maker side. The management apparatus collates the received ID information and positional information with the information stored in storage means of its own, and as a result, transmits the option software to the controller via a communication line if it is determined that there is no problem on transmission. And the option software is downloaded into the controller.