9XTend™
OEM
RF
Module
–
Product
Manual
v1.2.4
©
2005
MaxStream,
Inc.
Confidential
&
Proprietary
54
RS-485 (2-wire) Operation
DIP Switch Settings and Serial Port Connections
Figure
B.14.
Figure
B.15.
RS
‐
485
(2
‐
wire)
Half
‐
Duplex
Pins
used
on
the
female
RS
‐
232
(DB
‐
9)
DIP
Switch
Settings
Serial
Connector
Figure
B.16.
RS
‐
485
(2
‐
wire)
with
Termination
(optional)
Termination is the 120
Ω
resistor between T+ and T-.
DIP Switch settings are read and applied only while powering-on.
Note: Refer to Figures B.22 and B.23 for RJ-45 connector pin designations used in
RS-485/422
environments.
Table
B.6.
RS
‐
485
(2
‐
wire
half
‐
duplex)
Signals
and
their
implementations
on
the
XTend
Module
Assembly
DB-9 Pin
RS-485 Name
Description
Implementation
2
T/R- (TRA)
Negative Data Line
Transmit serial data to and from the
XTend Module Assembly
5 GND Ground
Signal
Ground
8
T/R+ (TRB)
Positive Data Line
Transmit serial data to and from the
XTend Module Assembly
9 PWR
Power
Optional power input that is connected internally
to the front power connector
1, 3, 4, 6, 7
not used
Wiring Diagram: RS-485 (2-wire) Half-Duplex
Figure
B.17.
XTend
Module
Assembly
in
an
RS
‐
485
(2
‐
wire)
half
‐
duplex
environment
