GF82.85-P-3114-08RM Operating, Display Unit With Control Unit, Function

GF82.85-P-3114-08RM Operating, Display Unit With Control Unit, Function
- with CODE (527) COMAND APS (with navigation)


Processing button actuations
The control buttons and switches on the function keypad on the COMAND operating, display and control unit (A40/3) are read in over the microcontroller I and O ports and transferred to the central processor. Depending on the system function, the button operations are processed further in the central computer or are signaled to the other system components via the Media Oriented System Transport (MOST) and the Controller Area Network bus class B (interior) (CAN-B) in the form of a data telegram.

Graphic editing and image output
The video subsystem takes over editing and output of the control displays. The control displays are internally output by the graphics subsystem to the display via the Color Video Blank Sync (CVBS) signal input. The information and amplitudes of the 3 basic colors red, green and blue as well as a synchronization signal are included in the CVBS signal. The electronic circuitry in the display unit evaluates the CVBS signal and actuates the individual display dots line by line.

There is a pulse at the end of each line which synchronizes the horizontal video signal. The electronic circuitry of the display unit then starts the next line. Upon reaching the last line, a pulse is received that synchronizes the vertical picture signal causing the electronic circuitry to start the first line again.

Diagnostic interface and fault management
While the COMAND operating, display and control unit (A40/3) is active, the system saves all faults that occur in the non-volatile memory. These faults can be read out using STAR DIAGNOSIS via the data link connector (X11/4). Output of the errors on the display unit is not possible. The diagnosis also includes the components that are connected to the MOST ring. Each MOST component has its own fault memory. The errors are transmitted to the audio gateway control unit (N93/1) when they are requested by STAR DIAGNOSIS via the MOST and can then be read out.

Digital versatile disk (DVD) ROM drive
With the aid of the integrate DVD ROM drive, it is possible to play audio CDs, video DVDs or MP3s.

The traffic data memory
The integrated traffic data recorder receives the traffic information by the radio tuner in the audio gateway control unit (N93/1) via the MOST. The data is stored for a maximum of 30 minutes in the traffic data recorder (up to 100 messages) even during the run-on time of the COMAND operating, display and control unit (A40/3). The traffic data recorder decodes the messages and transmits them to the navigation processor (N41/1) as required

The traffic data recorder requires an up-to-date location list from the navigation processor (N41/1) for synchronization purposes. The monitoring points for checking the network of roads (e.g. freeway exit) are defined by clear numbers in this location list. The location list is stored on the navigation DVD. It is loaded automatically (e.g. if DVD is changed) from the navigation processor (N41/1) into the non-volatile traffic data recorder.