SIERRA VIDEO SYSTEMS
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command to find out which single-dimensional array variables a particular router actually
supports, and what the valid index range is. Refer to documentation for each router for a
description of the variables.
A variable value is typically an unsigned decimal number, but may also be a signed decimal
number. The “G VAR1QRY” command can be used to determine the allowed range of values.
For example, to query for the value of the fifth element of an array variable named
“SYNC_SOURCE”:
** G VAR1,SYNC_SOURCE,5~ !!
The response command (or a command to set the variable to this value) might be:
** G VAR1,SYNC_SOURCE,5,3~ !!
VAR2: Modify or query two-dimensional array variables
Action
From Syntax
Modify
Host
G
VAR2,<varname>,<index1>,<index2>,<value>[,<value>…]~
Query
Host G
VAR2,<varname>,<index1>,<index2>~
Query Response
Router (same as Modify)
Modify is Protected:
Yes
Report Changes:
No
The “G VAR2“ command is used to change or query two-dimensional array variables that control
specific features of the router. The variable being affected is specified using its name and two
array indexes that vary from minimum values (typically 0 or 1) to some maximum values, and only
one such variable at a time can be targeted by this command. The features being controlled are
typically options that allow the user to control special hardware or software enhancements as a
function of router level and either input or output number, although the array variable is general-
purpose in nature and will be used whenever a two-dimensional array is appropriate.
The
Modify
command has four or more arguments, the name of the array variable to be changed,
the two indexes within the array of the variable to be changed, and the new value of that variable.
Most variables have only a single value associated with them, but it is possible for a variable to
be multi-valued, in which case the number of <value> arguments may be two or more.
The
Query
command has the name and the two indexes of the array variable whose value is to
be queried as its three arguments.
The
Query Response
command has the same argument structure as the
Modify
command.
Each different router may support different two-dimensional array variables. The supported two-
dimensional array variables may grow over time, as enhancements are added to this protocol, so
command parsers should generally ignore unknown variable names and out-of-range index
values. The routers themselves will ignore any command that is received with an unknown
variable name, with an index that is out of range, or an invalid variable value. Use the “G
VAR2QRY” command to find out which two-dimensional array variables a particular router
actually supports, and what the valid index range is. Refer to documentation for each router for a
description of the variables.