User`s manual

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A router may be sent “G” commands that it doesn’t understand. It will simply ignore them and
generate an ERROR response.
VAR: Modify or query system variables
Action From Syntax
Modify Host G VAR,<varname>,<value>[,<value>…]~
Query Host G VAR,<varname>~
Query Response Router (same as Modify)
Modify is Protected: Yes
Report Changes: No
The “G VAR“ command is used to change or query system variables that control specific features
of the router. The variable being affected is specified using its name, and only one variable at a
time can be targeted by this command. The features being controlled are typically system
options that allow the user to control special hardware or software enhancements to the router
code.
The Modify command has two or more arguments, the name 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 variable name whose value is to be queried as the only argument.
The Query Response command has the same argument structure as the Modify command.
Each different router may support different variables. The supported variables may grow over
time, as enhancements are added to this protocol, so command parsers should generally ignore
unknown variable names. The routers themselves will ignore any command that is received with
an unknown variable name or an invalid variable value. Use the “G VARQRY” command to find
out which variables a particular router actually supports. 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 VARQRY” command can be used to determine the allowed range of values.
For example, to query for the value of a variable named “VI_DELAY”:
** G VAR,VI_DELAY~ !!
The response command might be:
** G VAR,VI_DELAY,4~ !!
To set the “HD_SLAVE” variable to 1:
** G VAR,HD_SLAVE,1~ !!
VAR1: Modify or query single-dimensional array variables
Action From Syntax
Modify Host G
VAR1,<varname>,<index>,<value>[,<value>…]~
Query Host G VAR1,<varname>,<index>~
Query Response Router (same as Modify)
Modify is Protected: Yes
Report Changes: No
The “G VAR1“ command is used to change or query single-dimensional array variables that
control specific features of the router. The variable being affected is specified using its name and
an array index that varies from a minimum value (typically 0 or 1) to some maximum value, 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, input number, or output number, although the array variable is general-
purpose in nature and will be used whenever a single-dimensional array is appropriate.