Westermo TR-36B : User guide : Page 26

Application example

… TR-36 connected to TR-36 with DTR signal call

Configure the units

AT&F Set the unit to factory default.

AT&W Store default settings.

Set up the connection – The dialling modem

AT&Z0=”nnn” Store the number of the remote modem in the dialling TR-36.

AT&S0 Set DSR signal always high (if this signal is used to trig the DTR).

AT&B1 Activates automatic DTR dialling if DTR switches from low (OFF) to high (ON).

AT&W Save settings.

Switch DTR

from OFF

to ON

The modem will now dial the phone number stored in the first location of the

telephone number table (AT&Z0=<nnn>)

Set up the connection – The answering modem

ATA Enter the answer command when RING comes from the

network or set up ATS0=1 to auto answer on 1 RING signal

(or more than 1).

PSTN

Network

Relay

External

application

10 kohm

May be required in harsh environments.

NOTE: If no valid DTR signal can be provided by external application, the modems DSR signal can

be used to trig the transmission. Connect the DSR signal via a relay, or other potential

free contact, to the DTR signal. A 10 kohm pull down resistor should also be connected

between the DTR and a signal that is always low e.g. the DCD.