Specifications

Engineering Standard –NSW
Signalling SMS 02
Cerberus Level Crossing Monitor Equipment
March 2005 Version 1.2 © Australian Rail Track Corporation Page 48 of 118
This document is uncontrolled when printed.
Generally the configuration of the modem is set for the following features
to operate correctly with the level crossing monitor.
Recall the factory default settings.
Set the modem to autoanswer after 2 rings
Set carrier detect control to follow phone line data carrier, this is required
to operate the level crossing monitor correctly
Enable hanging up the modem using the DTR control line.
Disable response codes 7 & 8 so that the modem will not abort call if line
is busy. (this may be required with railway exchange/PABXs, put it in
anyhow)
Disable flow control
Disable MNP error correction and data compression Disable the echoing
of commands back to the local terminal Quiet mode, No echo
Save this new configuration to non volatile memory so that this
configuration is remembered even with the modem switched off.
Details of the cable that connects the modem to either a Personal
Computer or to the Level Crossing Monitor are given in drawing M08-
863 Modem Cable.
Note that if the modem initialisation string is set correctly in the Level
Crossing monitor then the level crossing monitor, at start up
automatically reconfigures the modem connected to the A serial port.
Note Make sure the number ‘0’ is a zero and not a letter ‘O’ in the
modem configuration string.
3.8.1 DPX-223 Modem
For the Dataplex DPX-223 the following commands the following modem
initialisation string is required.
AT &F &C1 &D2 S0=2 Q1 E0 &E0 &K0 X2 &W
Serial port A is set for 9600bps to provide consistency.
3.8.2 DPX-213 Modem
For the Dataplex DPX-213 the following commands the following modem
initialisation string is required.
AT &F &C1 &D2 S0=2 Q1 E0 &E0 &K0 X2 &W
The DPX-213 modem requires the serial port A to be set at 9600bps. It
will not operate at 19200bps.