GF82.85-P-3103-07SK Navigation Processor, Function
GF82.85-P-3103-07SK Navigation Processor, Function
- with CODE (527) COMAND APS (with navigation)
- with CODE (530) COMAND APS USA (with navigation system)
During navigation mode the navigation processor (N41/1) supplies all necessary data and information to the COMAND operating, display and control unit (A40/3). All the calculations for location finding, route calculation and navigation are performed in the navigation processor (N41/1).
Switching on/off characteristics
When the driver door is opened, navigation is already activated automatically via the Controller Area Network bus class B (interior) (CAN-B) and thus position finding is started. If no status change occurs at the electronic ignition switch control unit (N73) as a result, "circuit 15C" or "circuit 15R ON", the navigation computer remains activated (N41/1) for 30 minutes
Function conditions for route calculation and navigation:
^ Control unit within the specific temperature and voltage values
^ Circuit 15R ON
^ Media Oriented System Transport (MOST) activated
After shutting down the MOST ring the navigation processor (N41/1) remains in standby mode for 30 minutes, then it automatically goes into sleep mode. This also applies to the output of the data medium.
Only the data medium is accepted when a digital versatile disk (DVD) is inserted into the navigation processor (N41/1). No download, stand-by-mode or wake-up of the MOST is started.
The following information is included on the data medium:
^ Navigation data basis for location finding, route calculation and navigation
^ Data for dynamic navigation system
^ Data on map presentation
^ Index data base for destination and location for destination and location input
^ Expanded data for the journey guide data
^ Data for the voice output
Communication via MOST
As a component of the MOST ring, the navigation processor (N41/1) exchanges the entire information with other devices of the system via the MOST.
Software download
In the device a bootstrap driver which cannot be overwritten is stored as minimum equipment. The driver is able to load a software application from the navigation DVD. This ensures the compatibility between the navigation software and the database.
The software download process is triggered by the DVD, if differences in version between the flash memory and DVD are found. The progress of the update is indicated to the user by a progress display The navigation cannot be operated during this phase. The other components on the MOST are not influenced during this download.
External information
The audio gateway control unit (N93/1) supplies the information to the MOST, which is available on-board on the CAN B.
The following information is required as a minimum:
^ Circuit information (circuit 15R, door contact)
^ Wheel revolution and wheel direction of rotation
^ Diagnosis messages
Self-diagnosis
When the device is switched on and during operation the individual subfunctions and components of navigation are monitored. Faults are stored in the fault memory and can be read out during a service.
Destination memory, intermediate destinations and memory points
Destination storage, address books and interim destinations are not administered in the navigation component but in the COMAND operating, display and control unit (A40/3).
Map display
The map presentation is always controlled by the COMAND operating, display and control unit (A40/3).
Global positioning system (GPS) control unit
The GPS control unit is part of the navigation processor (N41/1). It evaluates the satellite signals coming from the GPS antenna (A2/23) and calculates the vehicle position from this information.
Yaw rate sensor
The yaw rate sensor (gyro sensor) determines the changes in direction of the vehicle. It is built into the navigation processor (N41/1). Calibration is not required.