Understanding Virtual Channel Definition Commands - Polycom SoundStructure C16 Design Manual

User-Defined Text Arguments
Text arguments and data that are user-defined (for example, virtual channel labels) support all UTF-8
symbols except the control symbols (0000-001F). The full range of UTF-8 symbols is supported to allow
user-definable labels in other languages. The control symbols are not supported because they are typically
unprintable. In particular, the line feed (000A) and carriage return (000D) symbols are not allowed for two
reasons: first, those symbols are used as command terminating characters; and second, the command set
does not support the concept of multi-line text arguments.
User-defined text arguments are delimited by a quotation mark symbol (0022) at the start and end of the
string. Quotation mark symbols appearing within the text argument can be escaped by a preceding
backslash symbol (005C). Literal backslash symbols appearing within the text argument are escaped by a
preceding backslash symbol.
Examples of valid user-defined test arguments are "Table Mics", "Mic 1\\3", and "\"Program\" Audio".
User-defined text arguments must be less than or equal to 256 bytes in length. Note that this may be less
than 256 symbols, since most of the UTF-8 symbols are multi-byte. The quotation mark delimiters and
escape characters are included in the 256 byte limit.
Acknowledgments
Control commands generate acknowledgments that are similar to the command format. The
acknowledgments are typically prefixed with the keyword val to indicate the value returned from the
command.

Understanding Virtual Channel Definition Commands

Virtual channel definition commands are a type of control command that provide methods for defining virtual
channels and mapping them to physical channels. The SoundStructure Studio software will create the virtual
channel definitions based on the input and output selections the designer has chosen. The syntax described
below is what SoundStructure Studio uses to create the channel definitions.
Channel definition commands support the following three actions.
vcdef
Define a new virtual channel and its physical channel mapping.
vcundef
Delete the definition of a virtual channel.
vcrename
Rename a virtual channel.
The syntax for each of these actions is given in the following sections.
vcdef Action
The vcdef action is a virtual channel definition command that defines a new virtual channel and its physical
channel mapping. Commands with the vcdef action have the following syntax.
vcdef <label> <vctype> <pctype> <num> [<num> ... ]<term>
Each of the command arguments is described in the following section.
<label>
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