访问 BDA 调谐器节点的频率属性

网络提供程序使用 KSPROPSETID_BdaFrequencyFilter 属性集来控制 BDA 筛选器拓扑中的 RF 调谐器节点。 例如，网络提供程序使用此属性集来通知调谐器节点如何优化 RF 信号。

在以下代码片段中，BDA 微型驱动程序中调谐器节点的控制引脚截获并为KSPROPSETID_BdaFrequencyFilter属性集的属性提供方法。 请注意，某些KSPROPSETID_BdaFrequencyFilter属性仅适用于特定类型的调谐器。

//
//  BDA RF Tune Frequency Filter
//
//  Defines the dispatch routines for the Properties
//  on the RF Tuner Node
//
DEFINE_KSPROPERTY_TABLE(RFNodeFrequencyProperties)
{
    DEFINE_KSPROPERTY_ITEM_BDA_RF_TUNER_FREQUENCY(
        CAntennaPin::GetCenterFrequency,
        CAntennaPin::PutCenterFrequency
        ),
    DEFINE_KSPROPERTY_ITEM_BDA_RF_TUNER_FREQUENCY_MULTIPLIER(
        NULL,
        CAntennaPin::PutFrequencyMultiplier // If this set handler 
        // is not called, the minidriver must determine that the 
        // frequency is in kHz. That is, the default multiplier is 
        // 1000 (1Hz x 1000).
        ),
#ifdef SATELLITE_TUNER // Only applicable to satellite tuners.
    DEFINE_KSPROPERTY_ITEM_BDA_RF_TUNER_POLARITY(
        NULL, NULL
        ),
    DEFINE_KSPROPERTY_ITEM_BDA_RF_TUNER_RANGE(
        NULL, NULL
        ),
#endif // SATELLITE_TUNER
#ifdef CHANNEL_BASED_TUNER // Only applicable to channel-based tuners.
    DEFINE_KSPROPERTY_ITEM_BDA_RF_TUNER_TRANSPONDER(
        NULL, NULL
        ),
#endif // CHANNEL_BASED_TUNER
#ifdef DVBT_TUNER // Only applicable to tuners that tune Digital Video Broadcast (DVB) signals.
    DEFINE_KSPROPERTY_ITEM_BDA_RF_TUNER_BANDWIDTH(
        NULL, NULL
        ),
#endif // DVBT_TUNER
};