Control Microsystems SCADAPack 350 Hardware Manual page 35

Pin Function
(Input)
6 TxD
(Output)
7 CTS
(Input)
8 RTS
(Output)
SCADAPack 350 Hardware Manual
February 14, 2007
Description
The LED is lit for a MARK level.
The level is SPACE on standby and MARK for transmitted
data.
The LED is lit for a MARK level.
This level must be a MARK for the communication port to
transmit data. When the attached device does not provide this
signal, the controller keeps the line at a MARK.
When the attached device does provide this signal, it must set
CTS to MARK to allow the controller to transmit data.
This pin is a MARK if full-duplex operation is selected for the
port.
This pin is set to a MARK just before and during transmission
of data if half-duplex operation is selected.
This pin is set to a SPACE when no data is being transmitted.
The LED is ON for a MARK level.
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