L-3 Communications CEU, User Manual

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STE User’s Manual Remote Control Operations
Rel. 2.6 8-7
digits received from the STE, the DTE must: escape from the On-Line State (via escape code or DTR
Escape Signal); issue the AT+S command to confirm the receipt of digits; then issue the AT+Z command
to read the digits. Received digits can only be read once; subsequent AT+Z commands, or commands
issued when no digits have been received, will return an ERROR result code. The AT+Z command can
return up to 64 digits. Digits are lost if they have not been read when a call is disconnected. Following
the result code return, the connection can be returned to On-Line State by the ATO0 command.
NOTE
(For TRI-TAC Operation)
To emulate DNVT keys, the STE converts your ‘ * ’ and ‘ # ’ keys of your keypad, to
‘R’ and to ‘C’ respectively. During secure dial, your STE HMI will display the
characters ‘R’ or ‘C’, but will convert them to ‘*’ or ‘#’ when secure digits are sent.
Secure digits cannot be dialed from any speed dial location. The keypad must be
used for all secure dialing.
8-5. AT INTERFACE
All call processing is performed under control of a control device (DTE) connected to RED SERIAL DATA
PORT 1 using AT commands customized for the STE.
8-5.1 General Rules of Operation
The STE AT interface is similar to commercial modem interfaces. If all commands on a command line are
successfully processed, only the result code for the last command is returned. Informational responses
are returned for every command, as appropriate. Some of the rules of operation are:
•
Multiple commands can be included on one command line as long as the command line does not
exceed 40 characters excluding the “AT”, line termination and space characters.
•
Multiple commands on a command line are processed in the order received.
•
Spaces in the command line are ignored.
•
Backspace characters, as defined by S5, in command lines cause the STE to ignore the
character preceding the backspace character. Multiple contiguous backspace characters are
supported.
•
If the STE does not execute a command on a command line, it will return an ERROR result code
to the control device and ignore any remaining commands on that command line.
•
Both upper and lower case AT commands are allowed as long as the A and T are the same case.
•
The STE will assume a 0 (zero) character at the end of a command if no number is present (e.g.,
AT+C0 and AT+C are equivalent commands).
•
All S-registers are 8 bits wide with the bits numbered from 0 to 7, right to left, with bit 0 being the
least significant bit (LSB) and bit 7 being the most significant bit (MSB).
•
Commands that modify S-registers produce the same result as writing the associated value to the
S-register.
•
RED DATA PORT 1 operates at 38.4 or 115.2 kbps as defined by local mode menu options at all
times except when in synchronous traffic mode.
•
Switching to synchronous traffic occurs following the CONNECT result code. Switching from
synchronous traffic occurs following an Escape Signal.
•
When in Voice Traffic State, the STE will hold the RED DATA PORT 1 received data signal (to
the control device) in the marking condition (will not send any characters) and will only respond to
an Escape Code on the transmit data signal (from the control device).
•
Setting the STE into Remote Control sets all S-registers to their default states.
8-5.2 AT Commands
The STE accepts AT commands from the control device connected at RED SERIAL DATA PORT 1 . All
commands result in either an “OK” or “ERROR” result code being returned to the control device, unless
otherwise noted.