Additional navigation functions and navigation displays

The functions of the Mk-3 navigation computer have been supplemented by navigation functions and navigation displays. The displays are shown on a larger screen on the Central Information Display (CID).

Brief description of components

Navigation computer / control unit

The navigation computer is fitted under the left-hand rear seat. The navigation computer is the platform for navigation and online services. The navigation computer is connected to the MOST bus (Media Oriented System Transport). The connection is via a standardized MOST transceiver. The MOST transceiver contains two nodes (interfaces). Every MOST message is composed of the following three parts:

• Control data
  
• Asynchronous data (e.g. navigation system, arrow representation)
  
• Synchronous data (e.g. audio, TV, video signals)
  

As a node is only able to evaluate two signals simultaneously, two nodes have to be used.

In the MOST framework, the navigation computer also performs controller functions.

The inputs at the navigation computer/control unit are:

• GPS aerial signal
  
• Speed signal (as processed signal from the DSC control unit)
  
• CVBS signal from the video module (is only converted and routed via RGB line to the Control Display)
  
• MOST data: The navigation computer is wakened by light across the MOST framework. The receiver must be operated permanently. The quiescent current is less than 0.02 mA.
  

The outputs at the navigation computer/control unit are:

• RGB signal (colour value signal red, green, blue) for map display. These signals are transferred directly to the Control Display by the navigation computer via the RGB line.
  
• MOST data as vector data for arrow representation at the instrument cluster and/or Central Information Display (CID).
  

Control Display (CD) and Central Information Display (CID)

The Control Display (CD) and Central Information Display (CID) are separate components. The Control Display (CD) with the Central Information Display (CID) and the Controller (CON) contains the operation and display elements for the vehicle electronics, with the exception of the ADP functions.

The Control Display (CD) co-ordinates the function requests from the system and assigns them to the individual functions. For the Control Display (CD), the following is displayed on the tester:

• CD Control Display
  
• CD GW Control Display (Gateway)
  

The Central Information Display (CID) is the display unit. For the Central Information Display (CID), the following is displayed on the tester:

• CID Central Information Display
  

Controller (CON)

The Controller (CON) is the control element for the Control Display (CD) with the display unit Central Information Display (CID). To run operating functions, the front Controller (CON) is folded out of the centre armrest.

Instrument cluster

On the instrument cluster, in conjunction with the navigation display on the Central Information Display (CID), navigation displays can also be shown.

Audio System Controller (ASK)

The audio system controller (ASK) is a control unit in the MOST network. The ASK audio system controller manages all the audio signals.

Main functions

The information is displayed in the Central Information Display (CID) and in the instrument cluster.

Route guidance

If the ”Route guidance” function has been activated, the navigation display is shown automatically as follows:

• In the instrument cluster at the revolution counter. In this function, the display cannot be switched off.
  
• In the Central Information Display (CID) on the button and RGB image bar. The display can be switched off by selecting other functions.
  

Map and arrow representations

• Map and arrow representation: The arrow representation is shown on the button and RGB image bar in the Central Information Display (CID) and the corresponding map section is shown in the Assistance window.
  
• Map or arrow representation and radio menu: In the Assistance window, a map or arrow representation is always possible. Simultaneously , the radio menu can be displayed on the button and RGB image bar.
  

Recalculation of route

Following a deviation from the planned route and before the next instruction screen, only a partial route and not the entire route is newly planned. This means than a recalculation of the route can be very fast.

Map display and map setup

Due to the anti-aliasing process, the image in the map display is brighter and the lines are displayed as more rounded. The faster screen/map setup is the result of hardware alterations in the navigation computer.

Route criteria and destination displays

• With the ”Route selection” function, the criterion ”Avoid tolls” can be applied.
  
• With the ”Destination list” function, several individual destinations can be grouped to form a destination list. These destinations are pursued successively.
  
• A message list of traffic disruptions can be displayed on the RGB image bar.
  
• With the ”Address book” function, selection of ”Direct destination home” enables display and modification of the home address. The destination list used until that time is deleted. (”Direct destination home” can also be activated by voice input.)
  
• With the ”New route” function, road blocks are possible. With ”Block route”, individual roads can be blocked. ”Block sections” blocks entire sections of road.
  
• Route information arrows, distance data and name of the next road are displayed in the instrument cluster in the revolution counter.
  

Help texts for menu items

Help texts can be displayed for the menu items shown on the menu bar (e.g. Route guidance).

Voice input and voice output

• Expansion of voice output has enabled the provision of information, e.g. ”Continue straight ahead, follow the M9”.
  
• Expansion of voice input means that functions can be activated, e.g. ”Direct destination home”.
  

A destination programmed by voice input can also be called up by voice input.

Service notes

• In the Control Display (CD) self-test, both nodes of the MOST transceiver are displayed as control units. One node, however, can only be displayed as ”Control unit recognized”. The second node is always on ”wait” (normally ”Control unit not recognized”)
  
• The Control Display (CD) knows how many MOST nodes (MOST chips) there are on the MOST ring bus. When retrieving the list of MOST control units fitted, the Control Display waits for a response from each MOST node. The query that leads the two MOST chips to the list is answered by only one of the MOST chips in the navigation system control unit. The responding MOST chip is represented as ”Navigation” and the other as ”wait”. This entry is not an error, but conversely cannot be suppressed.