Sierra Wireless MP 700 Series, Справочник по командам

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MP 700 Series GPS AT Command Reference
Note: A transition to command
state from data state does not
require that the session be
closed. This means that DCD will
remain asserted while the
modem is in command state,
online condition.
Offline Disconnected from any remote terminal or network
(on-hook). While in offline condition, the modem can only be
in command state (without an airlink).
The following tables show the possible combinations of
modes, states, and conditions:
Table 2-1: Functional combinations of modem state
and mode
Command State Data State
CSD Mode Yes Yes
GPRS Mode Yes Yes
Voice Mode Yes No
Table 2-2: Functional combinations of modem state
and condition
Command State Data State
Online Condition Yes Yes
Offline Condition Yes No
State Transitions
The auto connect feature (see
!MPPADSETUP
on page 54) deter­
mines what state is established when the modem is powered:
• If autoconnect is enabled, on start-up the modem is in data
state. (A PAD session is established, but not necessarily an
Internet connection.)
• If autoconnect is disabled, on start-up the modem is in
command state.
Command to data state
The modem changes from command to data state when a
session is opened either by dialing a connection, or by
answering a data call. When a session opens, the modem
issues the
CONNECT
message and, depending on the DCD
setting (see page 58), asserts the DCD control signal.
Data to command state
The modem changes from data to command state when:
• The DTR de-asserts (depending on settings made,
&D1
or
&D2
).
• The modem is reset or power-cycled (if autoconnect is
disabled).
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