GTWIN Reference Manual
2.2 Port
For COM port and TOOL port, the following terms need explanation:
GT Unit No.: Set the unit number for the GT unit when communication with an external
device is carried out in general purpose serial or Modbus Slave (RTU) mode.
Through: When the through function is being used, specify the the number of the PLC
with which communication is to take place.
2.2 Port
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