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GF82.85-P-3008RM Data Transfer Between COMAND and Instrument Cluster Function



GF82.85-P-3008RM Data Transfer Between COMAND And Instrument Cluster Function
- with CODE (527) COMAND APS (with navigation)

With the aid of the multifunction steering wheel (MFL) button and the left multifunction display (A1p13) of the instrument cluster (A1), the following systems controlled by the COMAND operating, display and control unit (A40/3) can be operated and information on the following systems displayed:
^ Audio system (e.g., radio tuner, CD player with changer (A2/6), etc.)
^ Navigation system
^ Telephone system

The entire data exchange between the instrument cluster (A1) and the COMAND operating, display and control unit (A40/3) takes place via the Controller Area Network bus class B (interior) (CAN B) and the Media Oriented System Transport (MOST). In the process, the audio gateway control unit (N93/1) serves as an interface between the CAN-B and the MOST.

All button actuations on the multifunction steering wheel (MFL) are read in by the instrument cluster (A1) directly voltage coded. The instrument cluster (A1) interprets these signals with the system (audio, navigation, telephone) currently displayed on the left multifunction display (A1p13). This interpretation is necessary, because the function of the buttons depends on the contents of the left multifunction display (A1p13). The interpreted data are subsequently read in by the instrument cluster (A1) on the CAN-B and received by the COMAND operating, display and control unit (A40/3) via the MOST.
The system change in the left multifunction display (A1p13) does not affect the representation in the display of the COMAND operating, display and control unit (A40/3); however, the change of the representation in the display of the COMAND operating, display and control unit (A40/3) does affect the left multifunction display (A1p13).


The instrument cluster (A1) receives the current time from the COMAND operating, display and control unit (A40/3) since this information is received automatically via the global positioning system (GPS).