Communication Protocols
37
"U": Automatic Output Change Reporting On/Off
Request: **U!! { 0 | 1 | 2 }
Response: (none)
Action: Turn automatic output change reporting off or on.
The command "U" turns on or off the automatic sending of output change
reports. The command letter must be followed by either a number 0, 1, or 2 to
specify the new automatic change report state, as follows:
* 0: Automatic output change reporting is turned off.
* 1 or 2: Automatic output change reporting is turned on, and crosspoint
change commands immediately report changed.
Output change reports are automatic messages sent to the host whenever an
output's crosspoint status (i.e. connected source) is change via either the local
control panel or via some other port.
Changes are reported in the same structure as described for the S command,
except there may be fewer lines to the report.
For example, the command:
**U1!!
turns on automatic output change reporting. The format of crosspoint
reporting is the same for U, S and ? messages.
"?": Query command
Request: **X5?!!
Response: **5,3,3,3,3!!<CR>
Action: The status of the previous command is requested.
The "? " Query can be added in a command string to cause a response back to
the host with selected status information.
The ? command can be placed in a shortened X command as illustrated
bellow to give the status of a single output.
**X5?!!
The ? command can be put at the end of a valid X command to give the status
of a switch after it is made. Such as
**X5,4,1?!!
In which case the response will confirm that that the above crosspoint
selection has been effected. Or it can be used multiple times in a command
string:
**X6?X5,4,1?!!