Fortunately the pin-out for most controls is standard for all controls. This pin-out description will determine the function for each pin. A pin-out description is usually supplied for each machine. These are the three pins that are needed for machine tool communications. For example one pin is used for transmission, another is used to receive data, and another is used for a ground.

The pins are numbered to distinguish one from the other. Each of the pins in a connector port has a different function. The connector will be 9 or 25 pin depending on the connector port configuration. A cable is used to connect the com port of the computer to the com port of the machine. This is done from the com port (RS-232) of the computer and the com port (RS-232) of the machine. The basics of machine tool communication are sending or receiving an NC program to or from a computer and a machine. BobCAD-CAM includes software for both sending and receiving and running DNC or a drip feed if the CNC machine is capable. 1 RS-232 Introduction Rs-232 is a method used for transferring programs to and from the CNC machine controller using a serial cable.

Bobcad 21 tool bar