Contec COM-2(PCI), User Manual

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External Connection
COM-2(PCI), COM-4(PCI), COM-8(PCI)
47
Connecting the Cable
The RS-232C interface requires that you use a different type of
cable depending on the type of device being connected. For
example, modem connections and computer (PC) connections
require different cables. Accordingly, check the specifications of
the external device to which you are connecting and select the
appropriate type of cable. The two types of cable are "straight-
through" and "crossed". Also, if the signal lines require
conditioning in the connector, provide conditioning in accordance
with the specifications.
External device
(Transmit Data)
(Receive Data)
(Request to Send)
(Clear to Send)
(Data Terminal Ready)
(Data Set Ready)
(Signal Ground)
TxD
RxD
RTS
CTS
DTR
DSR
SG
TxD
RxD
RTS
CTS
DTR
DSR
SG
Board
Figure 4.15. Example Connection to a Modem
Figure 4.16. Example Connection to a PC