Sierra Video Viper Component Series, User Manual

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SIERRA VIDEO
70
“U”: Update Request on/off
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: Automatic output change reporting is turned on. Crosspoint change commands do not
immediately report changed status, but instead, the report comes up to a few seconds
after the crosspoint change command is received.
2: Automatic output change reporting is turned on, and crosspoint change commands
immediately report changed status as part of the response to the command.
Output change reports are automatic messages sent to the host whenever an output is
crosspoint status (i.e. connected source) is changed.
For example, the command:
**U1!!
turns on automatic output change reporting. When a crosspoint is changed, the following
message might be received:
** X5,17,3 !!<CR>
indicating that output 5 is now connected to input 17 on level 3. Alternatively, if the router
has only a single level or if all levels of the output are connected the same, it might send:
** Y5,17 !!<CR>
indicating that output 5 is now connected to input 17. Alternatively, newer routers might
use the “V” command instead of “X” commands to report a change:
** V5,17,12,0 !!<CR>
indicating that output 5 is now connected to input 17 on level 1, to input 12 on level 2, and
does not exist or is not available on level 3.
To turn off output change reporting, use the command:
**U0!!
The difference between an argument value of 1 versus 2 has to do with the response
generated by the router when it receives a crosspoint connect command (“V”, “W”, “X”,
“Y”, or “Z” command). For example, suppose the router sends the following crosspoint
connect commands in a single command sequence:
** Y1,18 Y8,34 !!
If U1 is in effect, the response to this command will be:
** OK !!<CR>
and then sometime later, perhaps up to several seconds later, the crosspoint change
reports will be sent as separate command sequences for each output:
** Y1,18 !!<CR>
** Y8,34 !!<CR>
On the other hand, if U2 is in effect, the response to the original crosspoint change
command sequence will be:
** Y1,18 Y8,34 OK !!<CR>