DinBox PSTN Reference manual – V1.3
Bausch Datacom NV
14
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
2-wire signal flow
4-wire
4-wire signal flow
1
-
-
RCV/z
output – to DTE
2
B
in/out
XMIT/b
input – from DTE
3
A
in/out
XMIT/a
input – from DTE
4
-
-
RCV/y
output – to DTE
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.
- +
Power
Supply
x x
Not
Used
RS-485
4 3 2 1
Line
RJ-11
Serial DTE
RJ-45
RXD
TXD
DCD
WD
