Product manual

XStream-PKG-R™ RS-232/485 RF Modem – Product Manual v5.x00

2.2. RS-485 (2-wire) Operation

2.2.1. DIP Switch Settings and Pin Signals

Figure 2.6. Figure 2.7.

RS-485 (2-wire) Half-Duplex Pins used on the female RS-232 (DB-9)

DIP Switch Settings Serial Connector

Figure 2.8.

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 2.15 and 2.16 for RJ-45 connector pin designations used in

RS-485/422 environments.

Table 2.2. RS-485 (2-wire half-duplex) Signals and their implementations on the XStream RF Modem

DB-9 Pin

RS-485 Name

Description

Implementation

2 T/R- (TRA) Negative Data Line

Transmit serial data to and from the

XStream RF Modem

GND

Ground Signal

Ground

8 T/R+ (TRB) Positive Data Line

Transmit serial data to and from the

XStream RF Modem

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 2.9. XStream RF Modem in an RS-485 (2-wire) half-duplex environment