GF82.85-P-0003SK Cockpit Management and Data System (COMAND), Function

GF82.85-P-0003SK Cockpit Management And Data System (COMAND), Function
- with CODE (527) COMAND APS with single DVD drive (with navigation)

Component Identification:

Function
The COMAND operating, display and controller unit (A40/3) is the central control panel for the entertainment and communication systems integrated in the vehicle within the Media Oriented System Transport (MOST) ring system. All the system components and controls units involved can be selected and operated via the COMAND operating, display and controller unit (A40/3) and in addition, if included in the package, by the control buttons of the multifunction steering wheel (MFL). The COMAND operating, display and controller unit (A40/3) has a video-capable liquid crystal (LCD) color display for the output of information such as operating menu, map data for navigation and video picture. The COMAND operating, display and controller unit (A40/3) can be operated via 3 main control fields, which are located on the left and right next to the screen as well as below it, via a cross-shaped rocker button and a rotary switch.

Controls on the COMAND operating, display and controller unit (A40/3):
^ Permanently programmed function keys
^ Alphanumeric key block
^ Programmable function keys
^ Rotary switch with integral ON button
^ Direction input element with OK button
^ Voice repeat button for navigation
^ Mute button

Part of the controls are assigned with fixed functions, i.e. irrespective of the screen applied in each case they always trigger the same response. Several functions can be activated with the aid of the multifunction steering wheel buttons. However, these button operations are initially processed by the instrument cluster (A1). The instrument cluster (A1) links the incoming button actuations with the current menu setting on the upper multifunction display (A1p13) and the lower multifunction display (A1p15).

If necessary, it transmits a corresponding Controller Area Network (data bus/CAN bus) (CAN) message via the audio gateway control unit (N93/1) to the COMAND operating, display and controller unit (A40/3). The following functions can be operated centrally:
^ Radio mode
^ CD play mode
^ Navigation mode
^ RDS/TMC (dynamic destination-oriented navigation system, Germany)
^ telematics (telephone, SMS, WAP)
^ Voice control
^ Audio AUX
^ DVD video

Additional audio sources, e.g. an MP3 player, can be integrated into the front entertainment system using the audio AUX function. An AUX jack is located in the glove compartment as a connection facility.

Participating system components of the COMAND operating, display and controller unit (A40/3) with full equipment:
^ Audio gateway control unit (N93/1)
^ Universal Portable CTEL Interface (UPCI [UHI]) control unit (N123/1)
^ Navigation processor (N41/1)
^ Voice control system control unit (A35/11)
^ CD player with changer (in glove compartment) (A2/6)
^ Multifunction steering wheel (MFL)
^ Instrument cluster (A1)

MOST data bus system
The digital components of the COMAND operating, display and controller unit (A40/3) are interlinked through the MOST data bus system. The databus system is used to transmit data (control commands and useful information) between the various system components.

The audio signals (e.g. music from CD player with changer (in the glove compartment) (A2/6)) can also be transferred in this way. Because some of the individual components work with different data formats or require different data transfer rates and security levels, different data bus systems have been installed.
Data bus systems:
^ MOST
^ Controller area network bus class B (interior compartment) (CAN B)
^ Controller Area Network bus, class C (engine compartment) (CAN C)

Via the MOST data bus system, data/signals are exchanged between the audio gateway control unit (N93/1), the COMAND operating, display and controller unit (A40/3), the CD player with changer (in glove compartment) (A2/6), the Universal Portable CTEL Interface (UPCI [UHI]) control unit (N123/1) and the voice control system control unit (A35/11). The COMAND operating, display and controller unit (A40/3) communicates with other system components via the integrated MOST interface.

Interfaces
The CAN-B is used for data exchange with the instrument cluster (A1). In this manner the instrument cluster (A1) receives from the Audio gateway control unit (N93/1) via the COMAND operating, display and controller unit (A40/3) the Audio, telephone and navigation data for the upper multifunction display (A1p13) and lower multifunction display (A1p15) in the instrument cluster (A1) as well as the time via CAN-B.
Time synchronization between the COMAND operating, display and controller unit (A40/3) and the instrument cluster (A1) can also be performed via the multifunction steering wheel (MFL). The CAN-C is linked to the CAN-B via the central gateway control unit (N93) in order to receive data for location finding (e.g. dead reckoning). The data read in from the ESP and BAS control unit (N47-5) are placed on the CAN-C and are available on the CAN-B via the interface of the central gateway control unit (N93) and are therefore also available to the navigation processor (N41/1) via MOST.