MaxStream 9XTend, Product Manual

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9XTend™ OEM RF Module – Product Manual v1.2.4
© 2005 MaxStream, Inc. Confidential & Proprietary 55
RS-485 (4-wire) & RS-422 Operation
DIP Switch Settings and Serial Port Connections
Figure B.18. Figure B.19.
RS ‐ 485 (4 ‐ wire) and RS ‐ 422 Pins used on the female RS ‐ 232 (DB ‐ 9)
DIP Switch Settings Serial Connector
Figure B.20.
RS ‐ 485 (4 ‐ wire) & RS ‐ 422 with Termination (optional)
Termination is the 120 Ω resistor between T+ and T-.
DIP Switch settings are read and applied only while powering-on.
Table B.7. RS ‐ 485/422 (4 ‐ wire) Signals and their implementations with the XTend ‐ PKG ‐ R Module
Assembly
DB-9 Pin
RS-485/422
Name
Description Implementation
2 T- (TA)
Transmit Negative
Data Line
Serial data sent from the XTend Module Assembly
3 R- (RA)
Receive Negative
Data Line
Serial data received by the XTend Module Assembly
5 GND Signal Ground Ground
7 R+ (RB)
Receive Positive
Data Line
Serial data received by the XTend Module Assembly
8 T+ (TB)
Transmit Positive
Data Line
Serial data sent from the XTend Module Assembly
9 PWR Power
Optional power input that is connected internally
to the front power connector
1, 4, 6 not used
Wiring Diagram: RS-485 (4-wire) Half-Duplex
Figure B.21. XTend Module Assembly in an RS ‐ 485 (4 ‐ wire) environment