Rs-485 Interface; External Connections - Bausch Datacom DinBox PSTN Reference Manual

7.

RS-485 interface

The DinBox PSTN(485) has an internal RS-485 4-wire and 2-wire interface. See the
next chapters for more information about the use and setup of this interface.
7.1

External connections

The RS-485 interface must be connected via the screw contacts on the opposite side of
the power connection.
2-wire
1
-
2
B
3
A
4
-
See page 4 for the serial V.24 signal flow definitions in this manual. A modem is a DCE
device, receive is output and transmit is input !
In chapter 7.2 you will find a schematic overview of the RS-485 circuit.
In chapter 7.3 you will find an overview of the possible jumper settings.
Bausch Datacom NV
DinBox PSTN Reference manual – V1.3
2-wire signal flow
-
in/out
in/out
-
RS-485
4 3
WD
TXD
x
Not
Used
4-wire 4-wire signal flow
RCV/z
XMIT/b
XMIT/a
RCV/y
2 1
Line
RJ-11
DCD
RXD
Serial DTE
RJ-45
x - +
Power
Supply
14
output – to DTE
input – from DTE
input – from DTE
output – to DTE