Campbell CNL100, Инструкция по эксплуатации

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B-1
Appendix B. Null-Modem Cable
A null-modem cable allows communication between two similar devices. It is
sometimes called a crossover cable, because the transmit and receive lines are
crossed so that the two devices can communicate. An RS-232 null modem cable
usually also crosses other handshaking lines.
An RS-232 null-modem cable can be purchased at a local computer store. The
pin-outs for this cable are provided below.
Carrier Detect 1
⇔
4 Data Terminal Ready
Transmit Data
2
⇔
3
Receive Data
Receive Data
3
⇔
2
Transmit Data
Data Terminal Ready
4
⇔
1, 6
Carrier Detect, Data Set Ready
Signal Ground
5
⇔
5
Signal Ground
Data Set Ready
6
⇔
4
Data Terminal Ready
Request to Send
7
⇔
8
Clear to Send
Clear to Send
8
⇔
7
Request to Send
Not Used 9 9 Not Used