Accessory media player

Command Direction: media player→accessory Returns the title of the indexed playing track in response to a valid GetIndexedPlayingTrackTitle telegram from the accessory. GetIndexedPlayingTrackArtistName Command Direction: accessory→media player Applies to: playback engine Requests the name of the artist of the indexed playing track. In response to a valid telegram, the media player sends a ReturnIndexedPlayingTrackArtistName telegram to the accessory. ReturnIndexedPlayingTrackArtistName Command Direction: media player→accessory Returns the artist name of the indexed playing track in response to a valid GetIndexedPlayingTrackArtistName telegram from the accessory. GetIndexedPlayingTrackAlbumName Command Direction: accessory→media player Applies to: playback engine Requests the album name of the indexed playing track. ReturnIndexedPlayingTrackAlbumName Command Direction: media player→accessory Returns the album name of the indexed playing track in response to a valid GetIndexedPlayingTrackAlbumName telegram from the accessory. SetPlayStatusChangeNotification Command Direction: accessory→media player Applies to: playback engine Sets the state of play status change notifications from the media player to the accessory. PlayStatusChangeNotification Command Direction: media player→accessory The media player sends this telegram to the accessory when the media player play status changes, if the accessory has previously enabled notifications using the SetPlayStatusChangeNotification command. This telegram contains details about the new play status. PlayCurrent Selection Command Direction: accessory→media player Applies to: playback engine and database engines. This command copies items from the database engine to the playback engine. Requests playback of the currently selected track or list of tracks. PlayControl Command Direction: accessory→media player Applies to: playback engine Sets the new play state of the media player. GetShuffle Command Direction: accessory→media player Requests the current state of the media player shuffle setting. ReturnShuffle Command Direction: media player→accessory Returns the current state of the shuffle setting. SetShuffle Command Direction: accessory→media player Sets the media player shuffle mode. GetRepeat Command Direction: accessory→media player Requests the track repeat state of the media player. ReturnRepeat Command Direction: media player→accessory Returns the current media track repeat state to the accessory. SetRepeat Command Direction: accessory→media player Sets the repeat state of the media player. SetDisplayImage Command Direction: accessory—media player Sets a bitmap image that is shown on the media player display when it is connected to the accessory. GetMonoDisplayImageLimits Command Direction: accessory→media player Requests the limiting characteristics of the monochrome image that can be sent to the media player for display while it is connected to the accessory. ReturnMonoDisplayImageLimits Command Direction: media player→accessory Returns the limiting characteristics of the monochrome image that can be sent to the media player for

The media player. ReturnMediaPlayerName Command Direction: media player→accessory The media player sends this command in response to the RequestMediaPlayerName command message from the accessory. RequestMediaPlayerSerialNum Command Direction: accessory→media player Retrieves the serial number string of the media player. The media player responds with a ReturnMediaPlayerSerialNumber command containing the serial number. ReturnMediaPlayerSerialNum Command Direction: media player→accessory The media player sends this command in response to the RequestMediaPlayerSerialNumber command message from the accessory. RequestMediaPlayerModelNum Command Direction: accessory→media player Retrieves information for the media player. The media player responds with a ReturnMediaPlayerModelNum command containing the model number of the media player. ReturnMediaPlayerModelNum Command Direction: media player→accessory The media player sends this command in response to the RequestMediaPlayerModelNum command message from the accessory. IdentifyAccessoryLingoes Command Direction: accessory→media player The accessory sends this command to signal its presence and to identify its supported lingoes. In response, the media player sends an ACK command. The IdentifyAccessoryLingoes command is used by multi-lingo accessories to report all supported lingoes and should be used in place of the Identify command. GetDevAuthenticationInfo Command Direction: media player→accessory The media player sends this command to obtain authentication information from the accessory. The command is sent if and only if the accessory has indicated that it supports authentication in its IdentifyAccessoryLingoes Options bits and has passed a valid, non-zero accessory ID. In response, the accessory sends a RetDevAuthenticationInfo command. RetDevAuthenticationInfo Command Direction: accessory→media player The accessory indicates the MPAP authentication version that it supports by returning this command in response to a GetDevAuthenticationInfo command from the media player. AckDevAuthenticationInfo Command Direction: media player→accessory The media player sends this command in response to RetDevAuthenticationInfo command. It indicates the current state of the accessory authentication information. RequestLingoProtocolVersion Command Direction: accessory→media player Retrieves version information for any of the lingoes supported by the media player. The media player responds with a ReturnLingoProtocolVersion command containing the major and minor version information of the requested media player lingo. ReturnLingoProtocolVersion Command Direction: media player→accessory The media player sends this command in response to the RequestLingoProtocolVersion command message from the accessory. The major and minor version information for the requested lingo are returned. GetDevAuthenticationSignature Command Direction: media player→accessory The media player sends this command to authenticate a accessory that has identified itself as requiring authentication. Authentication occurs either immediately upon identification or when the accessory attempts to use a restricted lingo or command. The accessory calculates its digital signature based

On the challenge offered by the media player and sends the results back to the media player using a RetDevAuthenticationSignature command. If the returned signature cannot be verified, the media player responds with a non-zero AckDevAuthenticationStatus command, followed immediately by another GetDevAuthenticationSignature command. RetDevAuthenticationSignature Command Direction: accessory→media player The accessory sends this command to the media player in response to GetDevAuthenticationSignature command. The media player verifies the digital signature, calculated by the accessory based on the offered challenge. If verification passes, the media player authenticates the accessory and updates its lingo and command access permissions accordingly. The authentication status is sent to the accessory using AckDevAuthenticationStatus command. AckDevAuthenticationStatus Command Direction: media player→accessory The media player sends this command to the accessory in response to the RetDevAuthenticationSignature command. It indicates the current accessory authentication state. If the accessory receives a non-zero status, the accessory has failed authentication and will only be able to use unauthenticated lingo commands. If the accessory receives a zero status, the media player has successfully authenticated the accessory. The accessory may then use the requested authenticated lingoes and commands. Optionally, the accessory may begin the process of authenticating the media player, by sending a GetMediaPlayerAuthentication command. GetMediaPlayerAuthenticationSignature Command Direction: accessory→media player The accessory uses this command to send an offered challenge to the media player for digital signature. In response, the media player returns its signed challenge to the accessory using RetMediaPlayerAuthenticationSignature command. Accessories should implement the authentication retry feature described in GetDevAuthenticationSignature command. RetMediaPlayerAuthenticationSignature Command Direction: media player→accessory The media player sends this command to the accessory in response to a Get MediaPlayerAuthenticationSignature command. The accessory verifies the digital signature, calculated by the media player based on the offered challenge, and, if verification passes, authenticates the media player. The accessory sends the authentication status to the media player. AckMediaPlayerAuthenticationStatus Command Direction: accessory→media player The accessory sends this command to the media player in response to RetMediaPlayerAuthenticationSignature command. It indicates the current media player authentication state. The accessory should return a non-zero ACK for each failed authentication attempt. GetMediaPlayerAuthenticationInfo Command Direction: accessory→media player The accessory sends this command to obtain authentication information from the media player. The media player should send this command only if the accessory has indicated that it supports authentication in its IdentifyAccessoryLingoes command options bits and the media player has successfully completed the authentication process. In response, the media player sends RetMediaPlayerAuthenticationInfo command.

Returns the requested track information type and data. The media player sends this command in response to the GetIndexedPlayingTrackInfo command. RequestProtocolVersion Command Direction: accessory→media player Requests the version of the running Extended Interface protocol from the media player. The media player responds with a ReturnProtocolVersion command. ReturnProtocolVersion Command Direction: media player→accessory Returns the media player Extended Interface protocol version number. The media player sends this command in response to the RequestProtocolVersion command from the accessory. RequestMediaPlayerName Command Direction: accessory→media player Returns the name of the user's media player or “media player” if the media player name is undefined. This allows the media player name to be shown in the human-machine interface. ReturnMediaPlayerName Command Direction: media player→accessory The media player sends this command in response to the RequestMediaPlayerName telegram from the accessory. ResetDBSelection Command Direction: accessory→media player Applies to: database engine Resets the current database selection to an empty state and invalidates the category entry count. That is, it sets the count to 0 for all categories except the playlist category. SelectDBRecord Command Direction: accessory→media player Applies to: database engine. Selecting a single track automatically passes it to the playback engine. Selects one or more records in the database engine, based on a category relative index. GetNumberCategorizedDBRecords Command Direction: accessory→media player Applies to: database engine Retrieves the number of records in a particular database category. ReturnNumberCategorizedDBRecords Command Direction: media player→accessory Returns the number of database records matching the specified database category. RetrieveCategorizedDatabaseRecords Command Direction: accessory→media player Applies to: database engine Retrieves one or more database records from the media player, typically based on the results from the GetNumberCategorizedDBRecords command query. ReturnCategorizedDatabaseRecord Command Direction: media player→accessory Contains information for a single database record. GetPlayStatus Command Direction: accessory→media player Applies to: playback engine Requests the current media player playback status, allowing the accessory to display feedback to the user. ReturnPlayStatus Command Direction: media player→accessory Returns the current media player playback status. GetCurrentPlayingTrackIndex Command Direction: accessory→media player Applies to: playback engine Requests the playback engine index of the currently playing track. ReturnCurrentPlayingTrackIndex Command Direction: media player→accessory Returns the playback engine index of the current playing track in response to the GetCurrentPlayingTrackIndex telegram from the accessory. GetIndexedPlayingTrackTitle Command Direction: accessory→media player Applies to: playback engine Requests the title name of the indexed playing track from the media player. In response to a valid telegram, the media player sends a ReturnIndexedPlayingTrackTitle telegram to the accessory. ReturnIndexedPlayingTrackTitle