User`s manual

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CHAPTER 8 DATA COMMUNICATIONS USING HALF-DUPLEX COMMUNICATIONS
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8.3 Changing the Communication System
8.3 Changing the Communication System
To change the data communication mode from full-duplex communication to half-duplex communication, registration
on the GX Configurator-SC's "Transmission control and others system setting" screen is required.
The following explains setting items for changing the communication system.
(1) RS-232 communication system designation
Designate either full-duplex or half-duplex communication.
(2) Simultaneous transmission priority/non-priority designation
When the Q series C24 and the external device start data transmission simultaneously in half-duplex mode,
designate whether to continue (priority) or stop (non-priority) transmission from the Q series C24.
Designated values "1" to "255" for setting "non-priority" will be the transmission wait time that elapses from when
the resumption of data transmission becomes available until data is actually sent.
(3) Retransmission time transmission method designation
When "half-duplex communication" and "non-priority" are set as indicated above, this setting becomes valid.
When the Q series C24 and the external device begin transmission simultaneously, if the Q series C24 stops and
then restarts transmitting, designate whether the stopped message will be transmitted from the beginning
("resend") or whether transmission will continue after the stopped message ("not resend").
(4) RS-232 CD terminal check designation
When using half-duplex communication, set the "CD terminal check designation" to on.