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DIAL=
Modem dial string
(default, ATDT)
This is the command that must precede all numbers that the MODEM
has to dial. Typically the MODEM will dial using either pulse or tone
dialling. This is dependent on the telephone exchange the MODEM is
connected to, most modern exchanges are able to accept tone dialling
which is faster than the older pulse dialling method.
For tone dialling: DIAL=ATDT
For pulse dialling: DIAL=ATDP
has to dial. Typically the MODEM will dial using either pulse or tone
dialling. This is dependent on the telephone exchange the MODEM is
connected to, most modern exchanges are able to accept tone dialling
which is faster than the older pulse dialling method.
For tone dialling: DIAL=ATDT
For pulse dialling: DIAL=ATDP
Tip:
Extra information can be linked to the above commands, internal exchanges that
require a “9" to be dialled to access outside lines can have this added to the dial string,
typically ATDT9.
require a “9" to be dialled to access outside lines can have this added to the dial string,
typically ATDT9.
7.4
Modem Operation
All modern modems respond to a set of “Hayes” commands. There are several
differences in these commands from manufacturer to manufacturer. It is important to
use the correct commands with each modem and not to attempt to use one
manufacturer’s set up with another manufacturer’s modem.
differences in these commands from manufacturer to manufacturer. It is important to
use the correct commands with each modem and not to attempt to use one
manufacturer’s set up with another manufacturer’s modem.
If possible modems should be linked to DVST in the synchronous mode. Some
modems, for example those using PEP (Packet Ensemble Protocol), can only be used
in the asynchronous mode.
modems, for example those using PEP (Packet Ensemble Protocol), can only be used
in the asynchronous mode.
Cables for connection to synchronous and asynchronous modems are different and are
not interchangeable. Refer to the Cable Assemblies chapter for further details.
not interchangeable. Refer to the Cable Assemblies chapter for further details.
Dedicated Micros Ltd
Page 21
DVST Installation Guide
Modems