IPlfApiTuning
  1. General info
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    Analogue and Digital
    The tuning interface is used both for analogue and digital broadcast reception. Before using this interface, the client of the platform will have selected the tuner as a video and/or audio source using the function SelectVideoSource()/SelectAudioSource() in the Source module. With the designator parameter in the same function, the client also indicates whether an analogue or digital use case is selected. If a client of the platform calls SelectVideoSource()/SelectAudioSource() anew in the Source module, the use of the tuning interface for either analogue or digital broadcast reception can also change anew.
    Frequencies and channel numbers
    The 'frequency' denotes an exact position in a frequency band. A more abstract positioning is based upon channel numbers, where a 'channel' denotes a particular frequency including predefined lower and upper bound frequencies. The mapping of channel numbers to frequencies can be different per region or country. The channel table interface papi_fe_chantab provides means to select the regional or country specific channel table.
    Frequencies can be freely selected between minimum and maximum frequency, whereas channel tables provide a non-consecutive list (containing gaps) of possible channel numbers between minimum and maximum channel. So the frequency boundary limits are mainly depending on the tuner capabilities, whereas the selected channel table defines the channel boundary limits.
    Searching
    The tuner is also able to search for stations. The search process typically includes: . The search and tune operations result in a notification, notifying whether a station could or could not be found. The TV system is notified separately.
    Automatic Frequency Control - AFC
    Through AFC, the tuner continuously updates its frequency to track a possibly drifting transmitter (such as a VCR). AFC takes place in a predefined window, which is a configurable setting of the platform. Notifications are raised when the frequency changes significantly and if the limits of this window are reached. Note that no station found/not found notifications are raised.
    TV system detection
    The platform stays with the selected TV system unless the client of the platform sets a different TV system explicitly or triggers automatic TV system detection. Automatic TV system detection can be triggered in two ways: . TV system detection is always single shot: after a notification of the TV system that is detected, a client of the platform has to do a new request to start TV system detection anew. Without an explicit request to start TV detection, any change in TV system will not be detected by the platform as it assumes that the TV system remains unchanged.
    Any need for an initial or default (country-specific) TV system will be handled by an explict call to pApi.
    For additional information, see also the UHAPI Specification on Tuning.

    1. Constants
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    2. Functions/Parameters
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