Polycom SR12 Speaker System User Manual


 
Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12
A - 8
Controlling SoundStructure Parameters
The SoundStructure command and control functions allow an external
controller to set, query, and monitor parameters of one or more linked
SoundStructure devices. There are three types of parameters that can be
controlled:
system parameters,
virtual channel parameters, and
matrix parameters.
System Parameters
System parameters are global and apply to a collection of OBAM-linked
SoundStructure devices. A device-specific system parameter affects a
parameter on a single SoundStructure device. Examples of device specific
system parameters include firmware version and RS-232 baud rate.
Device-specific system parameters are addressed by an integer index that
indicates the device ID of the SoundStructure device that is to be controlled.
The device ID is created automatically when multiple SoundStructure devices
are linked together through the OBAM interface. All stand-alone
SoundStructure devices will have a device ID equal to 1. In a multi-device
system, the device that has no OBAM in connection is device 1, the device
connected to that device is device 2, and so on until the last device. Up to 8
devices may be connected over OBAM.
Virtual Channel Parameters
Virtual channel parameters are defined for a given virtual channel. Examples
of virtual channel parameters include gain, AEC enable, and telephone
dialing. These parameters are addressed by the virtual channel name that
identifies the virtual channel to be controlled.
Matrix Parameters
Matrix parameters are defined at crosspoints of the SoundStructure matrix
mixer. Since a matrix crosspoint is defined by an input and an output, matrix
parameters are addressed by two virtual channel names that identify the input
and output virtual channels that define the crosspoint to be controlled.
Parameters can have access modes of read/write, read-only, or write-only. Some
parameters can also support user-definable minimum and maximum limits
such as volume control commands.
All parameter control commands operate on a specific type of parameter. The
parameter types supported by the SoundStructure control protocol are: