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XStream-PKG-R™ RS-232/485 RF Modem – Product Manual v5.x00
2 .3 . RS- 4 8 5 ( 4 - w ir e ) a n d RS- 4 2 2 Ope r a t ion
2 .3 .1 . D I P Sw it ch Se t t in gs a n d Pin Sign a ls
Figure 2.10. Figure 2.11.
RS-485 (4-wire) and RS-422 Pins used on the female RS-232 (DB-9)
DIP Switch Settings Serial Connector
Figure 2.12.
RS-485 (4-wire) and RS-422 with Termination (optional)
Termination is the 120 Ω resistor between T+ and T
- .
DI P Sw it ch set t ings ar e r ead and applied only w hile pow er ing- on.
Table 2.3. RS-485/422 (4-wire) Signals and their implementations with the XStream-PKG-R RF Modem
DB-9 Pin
RS-485/422
Name
Description Implementation
2 T- (TA)
Transmit Negative
Data Line
Serial data sent from the XStream RF Modem
3 R- (RA)
Receive Negative
Data Line
Serial data received by the XStream RF Modem
5 GND Signal Ground Ground
7 R+ (RB)
Receive Positive
Data Line
Serial data received by the XStream RF Modem
8 T+ (TB)
Transmit Positive
Data Line
Serial data sent from the XStream RF Modem
9 PWR Power
Optional power input that is connected internally
to the front power connector
1, 4, 6 not used
W ir in g D ia gr a m : RS- 4 8 5 ( 4 - w ir e ) H a lf- D uple x
Figure 2.13. XStream RF Modem in an RS-485 (4-wire) environment
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