CD player with changer, function - GF82.64-P-3113-02TU
Control of CD changer
The CD changer (A2/6) is actuated via the Media Oriented System Transport (MOST) and an electric wake up line, depending on the vehicle equipment.
Compatible operating units:
- COMAND operating, display and control unit (A40/3)
The CD changer (A2/6) is moved out after the button under the hazard warning system switch (N72/1s5) in the upper control panel control unit (N72/1) is operated. This is automatically raised in the process and releases the input opening with the button panel.
The CD-changer (A2/6) produces messages on the following operating conditions:
- No magazine in CD changer
- Magazine occupation (music CDs only)
- Number of current CD
- Number of current title
- List of occupied slots (CDs)
- Track number per disk
- Current operating state (acoustic reproduction of radio signals, pause, etc.)
The messages are placed on the Media Oriented System Transport (MOST) and are displayed by the COMAND operating, display and control unit (A40/3).
CD playback
The audio data is stored digitally on the CD.- The audio CD in the CD player is driven by a motor. The laser optics scan the unwritten side of the rotating CD without touching it and convert the digital optical signals into electronic signals. Minor interruptions which occur on the audio CD due to scratches or contaminants are interpolated by the D/A converter and are thus adjusted.
The electronic signals are then decoded in the CD changer (A2/6) and are lead via the MOST (Media Oriented System Transport) to the COMAND operating, display and control unit (A40/3) and audio gateway control unit (N93/1).
All the control data such as input commands through the COMAND operating, display and control unit (A40/3) as well as the reply from the CD changer (A2/6) are shown on the display of the COMAND operating, display and control unit (A40/3).
The audio gateway control unit (N93/1) receives the audio data via the MOST (Media Oriented System Transport). The digitized data are processed here again and relayed to the vehicle speakers.
Jumps and interruptions during playback
When driving on poor roads and during strong vibrations it may be that jumps and interruptions occur during playback. In such cases, CD operation must wait until the road conditions improve.
Condensation can collect in the CD player housing when there are large fluctuations in ambient temperature. This may also lead to faults occurring during playback. In such cases it should be ensured that the CD changer (A2/6) is adequately ventilated.