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Chapter 6 – Initializing the GLC
GLC2400/2500/2600 Series User Manual
RI / VCC
Use this setting to specify the Expansion Serial Interface 9-pin to be at RI or VCC.
VCC is available only when the setting is at the operation mode. VCC will be
switched to RI when the operation mode is switched to the offline mode.
When the communication protocol for the Expansion Serial Interface is not
transferring, the setting is fixed to RI.
The SIO circuit can be damaged if a checking jig for the Expansion Se-
rial Interface is installed while VCC is selected.
COMMUNICATION FORMAT
Select one of the following options for the communication format: RS-232C, RS-
422 (4 line), or RS-422 (2 line).