Black Box IS425A, Руководство пользователя

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IS425A - ISDN Terminal Adapter with S/T-Interface
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However, it does not accept commands, except for the escape sequence
“+++”. When the link is lost or intentionally dropped the IS425A will
clear the call and re-enter the Command Mode.
The Call-in-Progress State
The Call-in-Progress state is the transition state between the Command
Mode and the On-Line state. After a call is placed, a connection must be
established within a preset period of time (S7 Register). If a connection
does not occur during the Call-in-Progress state, or if a key on the DTE
keyboard is pressed (a dial interrupt occurs), the IS425A will abandon the
call and re-enter the Command Mode.
The Escape Command Mode
Once the IS425A has entered the On-Line state, you may escape from this
state by entering the escape sequence “+++”. The escape sequence will
cause the IS425A to enter the
Escape Command Mode and respond with
the “OK” message. In the Escape Command Mode, most of the
commands can be invoked just as in the Command Mode. In the Escape
Command Mode the IS425A does not terminate the connection with the
remote side. To return to the On-Line state from the Escape Command
Mode, enter the command “ATO”.
9.3 Guidelines for Using AT Commands
All AT Commands (except the A/ command) begin with the AT prefix
and end with pressing the ENTER key. A typical AT Command line is
shown below.
AT Command String <Enter>
AT
•
The AT prefix is known as the “ Attention Characters .” It can be
uppercase or lowercase but the IS425A will not recognize a
combination of the cases (
At or aT ).
•
It also informs your terminal (IS425A) of your computer’s speed,
parity and character length. The data character formats (how your
data is structured) for the
AT Command set.