Chapter 4 Performance specification
4-8
If CD signal is not controlled by external devices, it must be connected in 3-wire type connection as in [Figure 4.6].
Recent PC does not control CD signal line, so when connecting with PC, it must be connected in 3-wire type.
[Figure 4.6] Connection of 3-wire type (without handshake)
Cnet(9-PIN)
Computer/communication
devices
Pin No.
Name
Connection No. and signal direction
Name
1 CD
CD
2 RXD
RXD
3 TXD
TXD
4 DTR
DTR
5 SG
SG
6 DSR
DSR
7 RTS
RTS
8 CTS
CTS
9 RI
RI
Remark
[Note1] When in null modem communication via RS-232C channel, wiring without handshake shall be
performed on the side of Cnet I/F module as in [Figure4.6] even if only 3 wires are used in
external devices.
[Note2] If not wired as in [Figure4.6], transmission in Cnet I/F module isn’t available, however, receiving
via Cnet I/F module is allowed.