The video module 5 Drive is the central processing unit for the video signals of the DVD changer and for the navigation device. However, the video module 5 Drive also ensures TV reception while driving. The video module 5 Drive is fitted with the special equipment 'Rear Entertainment' instead of video module 5.
The video module 5 Drive contains a number of TV tuners and has the following functions:
Inputs: In order to implement these functions, the video module 5 Drive is supplied with the necessary signals from various sources:
External source |
Signal |
Note |
|---|---|---|
DVD changer |
CVBS |
In the case of PAL 50 Hz, can be switched for NTSC to 60 Hz |
Navigation |
RGB |
Red-Green-Blue with synchronisation on the green channel |
Navigation, Japan |
RGBC |
RGB signal with external synchronisation signal |
Video AUX |
CVBS |
In the case of PAL / SECAM 50 Hz, can be switched for NSTC to 60 Hz. For special solutions of BMW Individual |
Internal source |
|
|
TV |
CVBS |
Converted into an RGB signal in the colour decoder |
Outputs: The video module 5 Drive has two outputs. The video module 5 Drive can place each source in parallel on both outputs or different sources on one output each.
The standard (PAL 50 Hz, NTSC 60 Hz) is transferred by the DVD changer with the control data via the MOST bus.
For the Video AUX input, depending on country variant, the standard for PAL and SECAM is set to 50 Hz and for NTSC to 60 Hz.
The standard can be changed using DISplus.
The video module 5 Drive is fitted in the luggage compartment, on the left beneath the navigation computer.
The video module 5 Drive is a self-diagnostic control unit in the MOST network.
Control Display: Apart from a few exceptions, the Control Display (CD) incorporates the controls and displays for the vehicle electronics. The Control Display coordinates the function requests from the system and assigns them to the relevant functions.
All functions of the video module 5 Drive can be displayed via RGB signals on the Control Display.
Controller: The Control Display is operated by means of the Controller located on the front centre armrest.
Rear Display: The Rear Display consists of a folding arm and an LCD display. The Rear Display is fitted symmetrically on the centre console and can be used for left-hand drive and right-hand drive vehicles. The Rear Display can be folded into the resting position and, to permit use of a skibag, can be folded downwards. A photocell is built into the Rear Display for measurement of the surrounding brightness. Depending on the surrounding brightness, the brightness of the LCD display is regulated (dimmed).
Only DVD video and TV signals from the video module 5 Drive can be displayed on the Rear Display (for series launch 03/2002).
Rear Controller: The Rear Controller is the control panel for operating the 'Rear Entertainment' functions on the Rear Display. Operation and structure of the Rear Controller are identical to those of the Controller in the front. However, the functions for front and rear are different.
The rear window incorporates aerials on both the left and right sides in the heated rear window.
To amplify the received TV signals, separate amplifiers are installed for the left and right aerials. The amplifiers are supplied with power by video module 5 Drive via the HF line.
The Audio System Controller (ASK) is a control unit in the MOST network. The ASK is the system master. The ASK is responsible for managing all audio signals.
The MOST (Media Oriented Systems Transport) bus links the audio, video and navigation systems. Information relating to function requests is transmitted to the relevant control units by means of MOST bus messages.
The video module 5 Drive is designed for worldwide reception of all TV standards and TV frequencies. The analog TV systems PAL, NTSC and SECAM are not suitable for TV reception while driving due to the TV channels involved and their principles of operation. In order to keep a picture steady while driving, a number of techniques must be applied. In the video module 5 Drive, the three-tuner concept, the diversity method and a picture stabilisation circuit are used.
In the video module 5 Drive, two main tuners and a background tuner are used.
Main tuner: Each main tuner has two aerial connections. As there are only two TV aerials in the vehicle, only one connection is used at each main tuner. Very fast switching between the inputs on the aerial branch with the best frequency in each case improves the reception quality. This ensures, also in the case of vehicle speeds > 80 km/h and disrupted reception conditions, that there is still adequate TV reception.
Background tuner: No separate aerial is connected to the background tuner. The background tuner is provided with signals by a main tuner. The background tuner searches continuously for alternative frequencies. The background tuner recognises alternative frequencies by the transmitted program label (e.g. ITV). Moreover, the list of receivable channels is automatically updated on a continuous basis.
In order to ensure the highest possible receiving power, the video module 5 Drive uses two diversity techniques.
Tuner diversity: The ”tuner diversity” function integrated in the video module 5 always selects the tuner whose aerial offers the best reception.
Frequency diversity: The ”frequency diversity” function integrated in the video module 5 always selects the best frequency of the selected channel if a number of frequencies are available.
The background tuner continuously searches through the entire frequency range for television reception and updates the channel list in the memory. There are two possibilities to search for alternative frequencies:
In order to improve the subjectively perceived picture quality, the vertical and horizontal impulses are regenerated. Here, the sync signals in the reception signal are selected, processed simultaneously and returned to the reception signal. This ensures that the picture remains stable on the display in the event of weak reception.
The video module 5 Drive has the necessary hardware for the videotext function. The video module 5 Drive is fitted with a videotext decoder and a memory for 1000 pages of videotext.
NOTE: The videotext function will be implemented at a later date.
The video module 5 Drive receives the TV sound via the aerial inputs in mono. The TV sound is output in mono on the right-hand and left-hand channel of the MOST bus.
The data duplicated in the video module 5 Drive is displayed on the Rear Display. The Rear Controller can be used to select other functions which are shown on the Rear Display (see: Rear Display functions).
The video module 5 Drive provides the following possibilities to operate the TV functions:
Picture settings: Can be changed on both displays:
Country settings: In order to receive the channels of the country in which the vehicle is located, a country setting can be performed. With this operation, the video module 5 Drive is switched over to the right TV standard or the right frequency grid.
Diversity ON/OFF: In the case of the ”Diversity through picture comparison” function, pseudo-alternative frequencies can occur due to similar picture content on different channels (e.g. a football game). If the video module 5 Drive erroneously assumes that a frequency is a true alternative frequency, the channel is changed.
NOTE: The diversity function can be deactivated in the Service menu. The change in setting is signalled to the video module 5 Drive via the MOST bus.
Channel list: The video module 5 Drive administers a channel list in which all currently receivable channels are displayed. The list is updated continuously. Insofar as the names of the individual channels can be determined, the list starts in alphabetical order with the channel names (BBC, ITV, SKY, etc.), followed by the channels where it was not possible to determine the name.These channels are listed with the designation of the channel in ascending order (CH3, CH7, CH12, etc.). If there are a number of channels of the same name (e.g. three times ITV), there are alternative frequencies.
If diversity is activated, the entry is only shown once in the list (ITV once). If the diversity function is deactivated, each channel is shown individually (ITV three times). The desired channel can be selected from the channel list on display.
The video module 5 Drive contains a flash memory for software updates via the flash connector. There is also a fault code memory for diagnostic purposes.