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Chapter 3: Installation
Table 3-2.
RJ-11 connector
Position
Function
1
No connection
2
RX+
3
TX+
4
TX-
5
RX-
6
No connection
Table 3-3. DB9 RS-232 connector
Pin–Signal
DCE Interface Function
(S1-A)
DTE Interface Function
(S1-B)
1 - Data Carrier
Detect
Output
Input
2 - Received Data
Output
Input
3 - Transmitted
Data
Input
Output
4 - Data Terminal
Ready
Input
Output
5 - Signal Ground
Ground
Ground
6 - Data Set Ready
Output (Pulled High)
Input (Pulled High)
7 - Request To
Send
Input (connected to pin 8) Output (connected to pin
8)
8 - Clear To Send
Output (connected to pin
7)
Input (connected to pin 7)
9 - Ring Indicator
Open
Open
DCE—Data Communications Equipment (can connect to a PC)
DTE—Data Terminal Equipment (configured the same as a PC)
NOTES:
1. When configured as DCE, Data Carrier Detect will be active when the remote
unit is driving the line.
