GF82.85-P-3103-07TU Navigation Processor, Function

GF82.85-P-3103-07TU Navigation Processor, Function
- with CODE (527) Navigation module for COMAND
- with CODE (528) HIGH Class USA

During navigation mode the navigation processor (N41/1) supplies all the 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
Simply opening the driver door activates the navigation system automatically via the interior CAN and thus initiates location finding. 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
^ MOST ring woken up

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

When a CD or DVD is loaded into the navigation processor (N41/1) only the data medium is accepted. No download, standby mode or wake-up of the MOST ring is started.

The following information is included on the data medium:
^ Navigation data basis for location finding, route calculation and navigation
^ 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
The information exchange between the navigation processor (N41/1) and other components takes place completely via the MOST ring.

Software download
As minimum equipment a bootstrap driver which cannot be overwritten is stored in the navigation processor (N41/1). 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 from the DVD becomes unstable if differences in version are found between the flash memory and DVD. The update process is displayed to the user.
The navigation cannot be operated during this phase.
Other components on the MOST ring are not influenced during this download.

External information
The audio gateway control unit (N93/1) supplies the information to the MOST ring which on the vehicle side is available on the interior CAN.

The following information is required as a minimum:
^ Circuit information (circuit 15R, circuit 15, 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 diagnostic trouble code memory.

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).

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 (A2/49a2) on model 211.0 or (A2/23) on model 211.2 and calculates from this the vehicle position.

Gyrosensor
The yaw rate sensor (gyro sensor) determines the change in direction of the vehicle. It is installed in the telecommunications control unit (N112). Calibration is not required.