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USWD500 User’s Manual Version 3.0
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DTR/DSR Operation Mode Setup
DTR
, (which means
Data Terminal Ready)
, is controlled from the host PC or
device. Pulsing DTR will disconnect your connection and return you to AT
command mode. There are three DTR operation modes for the USWD500
Modem. The commands for each mode are shown below:
AT&D0
DTR is ignored
AT&D1
Enter command state upon detecting
active-to-inactive transition of DTR.
AT&D2
Closes the connection upon detecting active-to-
inactive transition of DTR.
Equivalent to executing ATH2 command.
Auto-answer is disabled while DTR is inactive.
DSR
(which means
Data Set Ready)
, is sent out from the USWD500 Modem
under the following conditions:
AT&S0
DSR is always active
AT&S1
DSR following the state of the ”Connection
Established” condition.
Pulsing DTR is the preferred hardware method for hanging up or breaking your
(UDP) connection.
UDP Parameters Setup
The local socket port register
S80
is an important parameter for UDP mode. By
adjusting the
S80
register, you can define your own port number for the USWD500
Modem. Other users can then use this port number to communicate with your
USWD500 Modem in UDP mode. Don’t forget to store your modem’s register
configuration (
AT&W
) and reset your USWD500 Modem (
ATZ
) after changing the
port number of the
S80
register.
SPI/SPNI/WASI Parameters
SPI
(
Service
Provider
Identity
) is defined by socket port register
S61
. This
parameter is used by your service provider to determine whether your USWD500
Modem is legal.
SPNI
(
Service Provider Network Identity
) is defined by socket port register
S62
.
This parameter is used by your service provider to recognize what service network
can be issued to the users.
WASI
(
Wide Area Service Provider Identity
) is defined by socket port register
S63
. This parameter is used by your service provider to recognize users from