AudioControl 7.1 Channel THX Ultra 2 Theater Processor, Manual

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Maestro
tm
Phone 425-775-8461 • Fax 425-778-3166
®
Integration with Automation
Section
5-3
Protocol Structure
The RS-232 serial control protocol structure of the Maestro
is a string of ASCII characters terminated with an ASCII
Line Feed (0x0A hexadecimal). Multiple commands can be
linked together on one line separated by a semicolon, but
the total command string cannot contain more than 64
characters (including spaces and the Line Feed terminator).
In the following examples <lf> <lf> <lf> <lf> <lf> represents the ASCII Line
Feed. How you actually enter that character into your serial
control system varies by manufacturer. Check with their
programming information about direct ASCII character
entry.
Example:
To turn on the Maestro for Zone 1:
Z1PWR1<lf> <lf> <lf> <lf> <lf>
To turn on the Maestro and select the DVD source:
Z1PWR1;Z1AUD5<lf> <lf> <lf> <lf> <lf>
Command processing begins when the first semicolon
separator line feed terminator is received. When a com-
mand is executed properly, the Maestro echoes the
command back. If there is an error in the command, the
Maestro will return an error message of “FAIL”.
Control Commands
There are two types of serial control commands: Settings
and Queries. The Setting commands instruct the Maestro
to execute a function. The Query commands allow the
external control system to ask the Maestro the current
state of a function (i.e. Power, Mute, Input Source). To use
the query function, precede the command with a question
mark. Only a subset of all the serial commands have a
query function.
Example:
To query the current source selection for Zone 1:
?Z1AUD<lf> <lf> <lf> <lf> <lf>
If the DVD is currently selected, the Maestro will return:
Z1AUD5
Install Note: Install Note:
Install Note: Install Note: Install Note: Refer to Appendix “C”
for the complete listing of commands.