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7.0 AT Command Set
At any given time the WINC 900A is in either one of two modes, the command mode or the on-line
mode. When in the command mode, the device accepts commands from the host computer. These
commands are sent to the WINC 900A as character strings composed of printable ASCII characters.
Using the same character set, the WINC 900A responds to the host computer's command by sending
back a result code string indicating whether the WINC 900A was able to accomplish the requested
command.
The command language is based on the Hayes compatible and de facto industry standard AT
command set. In addition to the basic AT commands, certain command extensions accommodate
specific WINC 900A configuration requirements.
7.1 AT Command Syntax
A command line is a string of characters sent from the host computer or peripheral - Data Terminal
Equipment (DTE), to the WINC 900A - Data Communications Equipment (DCE). (The command
line is interpreted by the DCE only when in the command state.) All command lines have a prefix, a
body, and a terminator. The prefix consists of the characters "AT" and the body is a command string
restricted to the printable ASCII characters. The default terminator is the <CR> character and is
required for all commands except the A/ command. The WINC 900A accepts command strings that
adhere to the following rules:
(a) Commands begin with the two character sequence AT or A/. Any preceding characters are
ignored. The command line is terminated by the ASCII defined carriage return character
resident in register S3.
(b) Commands are accepted in upper and lower case.
(c) Multiple commands may be concatenated on the same command line, although blanks
(space character) may be inserted for readability and are ignored. Certain restrictions in
command sequencing on the same command line, as indicated below, must be followed.
(d) Unsupported commands or parameters return an ERROR result code to the host computer.
Any following commands on the same command line are ignored.
(e) Missing parameters default to the value 0 where expected.
(f) The command line may be edited prior to entering the command terminator with the
backspace character (register S5) or deleted entirely using the line cancel character
(ASCII CAN - Control X).
(g) The A/ command repeats the most recent command and requires no carriage return
terminator.
