Silex technology SX-550, Developer'S Reference Manual

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Standard AT Commands Supported
The following standard AT commands are interpreted by the device server. The data channel must be in
the command mode for commands to be recognized. The data channel will be in command mode upon
power up or reset.
There are two operating modes for the unit when the AT command option is enabled. In command mode,
data received from the serial port is passed to the AT command processor, and responses are returned to
the serial port. No data is sent to any network application, and any data received from the network is
ignored. In data mode, data from the serial port passes to the network application, and vice versa. This
is equivalent to the normal serial port operating mode without the AT command option.
Table 29 describes the AT Commands. Table 30 details the Extended AT Commands that allow the
configuration of the network server operating parameters. Any AT command received, except the listed
commands, are acknowledged with OK status. This allows existing modem applications to transmit
commands without causing an error. These include AT<X>n, but not currently AT&<X>n, AT%<X>n, AT\
<X>n, where <X> is a letter.
Table 29 AT Commands
Parameter Command Description
Enter Command mode <delay>+++<delay> If the ++ is seen in data mode, with no
characters sent for 1 second before or after, then
command mode is entered.
Initiate Connection Command ATD <destination> Standard modem dialing command, redefined to
initiate an internet connection to a remote computer.
Indicates the IP address of the target, and optionally
the TCP port number to use for connection. The T or
P option (ATDT or ATDP) can be present and has no
effect.
If present, the IP address must be exactly 12 decimal
digits with 3 for each byte of the address.
If no IP address is given, then the ecable destination
address defined for the port is used.
If the destination TCP port is defined, it is separated
from the IP address by a '#' character, and is 1 to 5
decimal digits.
If TCP port is defined, the ecable destination port
defined for the serial port is used. If the destination
port is 0, the standard Telnet port (23) is used.
If the destination string ends with a semicolon, the
server remains in the command mode, not the data
mode, once a connection is made.
In command mode data is not passed from the
remote computer, so data could be lost if the unit
stays in command mode.
If the connection cannot be attempted, NO CARRIER
status is returned. If the connection attempt fails, NO
ANSWER status is returned.
If the connection succeeds, CONNECT status is
returned.
Part Number 40183-101 Silex SX-550 Developer's Guide Page 71