Sierra Wireless MP 700 Series, Справочник по командам

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MP 700 Series GPS AT Command Reference
Note: If you are developing a
network application to control or
monitor MP 700 Series GPS
modems installed in a fleet of
vehicles, it is usually best to use
Always On mode. (With On
Demand mode, it can be difficult
to track the modems’ IP
addresses.)
Note: The AT command
AT!MPOPMODE
is used to set
the operating mode.
Modem-to-network connection
The operating mode determines how the modem-to-network
connection is established. In
Always On
mode, the modem-to-
network connection is established whenever the modem is
powered and GPRS/EDGE service is available. In
On Demand
mode, the modem-to-network connection is established only
when the host-to-modem connection is requested.
Regardless of the operating mode, the modem-to-network
connection is established as needed, if the modem has been
configured to send MTP data. (See the
AT!MPMTCONF
command on page 50.)
Host-to-modem connection
The MP 700 Series GPS supports serial and USB host connec­
tions. To issue AT commands to the modem, the serial
connection is required. Having a USB connection in addition to
the serial connection has two main advantages:
• USB provides a higher data rate between the host and the
modem
• With a USB connection, the modem connects instantly to
the network on startup. With only a serial connection, you
must establish the connection using Watcher or Windows
DUN (Dial-Up Networking.) With a USB host connection,
and the operating mode set to
Always On
, it is not necessary
to run Watcher or DUN to make connections.
If you intend to have both a serial and USB connection, you
must install the modem using the USB option. (When you
install the modem software, you are prompted to indicate
whether you are using a serial or USB connection. When you
select the USB option, both the serial and USB drivers are
installed.) If you install the modem using the serial option and
then connect a USB cable, the host computer will not be able to
communicate with the modem.
Modem modes, states, and
conditions
This document uses the words mode (circuit-switched data,
packet-switched data, fax, or voice), state (command or data), and
condition (online or offline)
to describe the modem’s operational
status.
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