Tripp Lite Keyspan USA-49WG Owner's Manual page 18

7.1.d – Serial Port Pin Outs
The pin assignments for the Keyspan USB 4 Port serial Adapter's male DB9 port are illustrated below:
Pin
1
2
3
4
5
6
7
8
9
In order to ensure compliance with emission specifications, cables, should be shielded using braided shields and
metal hoods with complete 100% contact between the shields and hoods.
External Loopback Connector Information
The Keyspan Serial Assistant allows you to perform two types of loopback tests – internal and external. The external
test requires the use of a special loopback connector. This connector requires a "DB9 Female Loopback plug" with
the following wiring:
Pin(s) Wired to
1 <->
2 <->
6 <->
Name Signal Designation
DCD Data Carrier Detect (Input)
RX Received Data (Input)
TX Transmitted Data (Output)
DTR Data Terminal Ready (Output)
GND Ground
DSR Data Set Ready (Input)
RTS Request To Send (Output)
CTS Clear To Send (Input)
RI Ring Indicator (Input)
Pin(s)
4, 8
3
7, 9
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