3 how to make a rs-232 connect cable – Q-See QSC26408 User Manual
Page 109
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User Manual for Commercial Series Net DVR
Page
109
Total
121
3 How to make a RS-232 connect cable
Material and tool
One twisted cable (8 pins), one standard RJ45 head, one or more DB25 or DB9 plug-ins, a
tool for RJ45, one electric iron, and some soldering tin.
Pin definition
Make the RJ45 according to the following pin definition; I means DVR input, O means DVR
output.
Pin index
Name
I/O
Description
1
DCD
I
Carrier Detect
2
RxD
I
Receive Data
3
TxD
O
Transfer Data
4
CTS
I
Clear Data
5
RTS
O
Request to Send
6
DTR
O
Terminal Device Ready
7
GND
Ground
8
Null
—
—
According to demand, the following three situations are considered to make the serial port
plug-in according to the corresponding relationship of the pin definition.
(1) When the serial port of the DVR is connected with the DTE device with DB25 plug-in
(terminal like computer, annunciator, door access etc), the corrresponding relationship is as
follows: