The GE Fanuc CNC controls Serial Cable Connection

The GE Fanuc CNC controls have a minimum of one serial communication port
available for communications. This port is designed to conform to the basic
requirements of the EIA232C standard. Connection to an EIA232 or EIA574
compliant device can be accomplished using a null modem cable.

Communication Cable Diagrams
EIA232C Null Modem Cable
This cable, utilizing a DB25P connector to a DB25S connector, uses Control
Codes also known as Software Handshaking. Controls and PG systems use
serial inter-face.

NOTE:
Pin #25 has 24 volts power supply on it. Do not use for normal interface
connection or damage to the control may occur.

EIA232C to EIA574 Null Modem Cable
This cable can be used for interfacing between IBM-compatible computers and
GE Fanuc controls. This cable uses a DB25P connector to a DB9S connector.
This is the most commonly used cable for communications and is available from
GE Fanuc or easily fabricated.