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Structure RTUSBAudioConfig

The USB Audio class driver has a few global options which it reads from structure RTUSBAudioConfig. The default values are given below. Applications can either modify selected values before the driver is registered or an alternate RTUSBAudioConfig structure can be linked.

typedef struct { 
   int Flags; 
   int MaxIOsPlay; 
   int MaxIOsRecord; 
} RTUSB32AudioConfig; 

RTUSB32AudioConfig RTUSBAudioConfig = { 
   0,       // Flags 
   2,       // MaxIOsPlay 
   2        // MaxIOsRecord 
};

There are currently no values defined for member Flags, which should be set to zero. MaxIOsPlay is the maximum number of I/O transactions the application can queue using function USBAudioPlay before calling USBAudioWaitDone. MaxIOsRecord is the maximum number of I/O transactions the application can queue using function USBAudioRecord before calling USBAudioWaitDone. Both values must be set to at least 2. Values higher that 16 are not recommended. With increasing MaxIOs... values, the CPU time requirement to play or record increases slightly. On the other hand, the real time requirement of the thread playing or recording is 1 - 1/MaxIO seconds (thus increases with MaxIOs...).

Function USBAudio