PURPOSE: To eliminate the necessity for a program change in an NC, following action correction or the like, and to cope with the correction only by description correction to an NC tape by performing a control of action parts excepts the shaft control of a machine tool through a digital input/output system for directly connecting an NC unit to the action part.
CONSTITUTION: A desired number of digital input/output interfaces 33 are provided in an NC unit 1, these interfaces are directly connected to an interface 34 of each accessary device 1:1 correspondingly, the input/output interface 33 is connected to a CPU24 of the NC unit 1 and a data of command, previously read by a tape reader 27, is stored in a RAM26 which constitutes the NC unit 1. In the case of continuously entering a command for waiting a limit switch Sa to be turned off, command for waiting a limit switch Sb to be turned off and a command for turning on an output of No. 10, in the CPU24, a lamp 6 is lighted by turning No. 10 to 1 when No. 1 is 1 and No. 2 is 0 in the interface.
YOSHIKAWA SHINJI
NAKAGAWA ATSUSHI
