BMW 7 Series: Car Information Computer

Fig. 5: Front View Of CIC

The design principle of the CIC is similar to a personal computer, the Car Information Computer contains a processor, RAM (memory) modules and other peripheral components.

The following CIC applications are stored on the integrated hard disk drive:

• Music collection
• Music track database (Gracenote)
• Navigation software (application)
• Navigation (map material)
• iSpeech (voice recognition system)
• Contacts (database with address data)
• System operating software

The CIC is the central control unit for the listed applications. It is linked to the central information display (CID) for the purpose of transmitting and displaying information.

The Car Information Computer is also connected to the controller. The controller serves as a selection and input device for the user interface.

The CIC is based on a modular design. The most important systems of the communication network are integrated in the CIC in the form of modules.

The CIC combines the following control units in one enclosure:

• Navigation computer, HIP module and yaw rate sensor
• Tuner (FM)
• Tuner (AM)
• Tuner (FM-TMC)
• IBOC decoder
• Audio system controller, and music search database
• MOST-CAN gateway
• Interface to control display (LVDS)

The upper half of the CIC consists of the optical drive player where CDs and DVDs of digital audio media can be played. The player also has ability to playback video DVDs on the front CID. The video signal is only displayed when the vehicle is stationary with the Parking Brake on.

For the navigation system, the optical drive can be used for updating the map material stored on the hard disk.

The processors for the main board and application board are located in the lower half of the CIC. This section also contains the main memory, the individual modules as well as the hard disk drive. The CIC together with the controller and CID, make up the iDrive system.

Advantages of the Car Information Computer

Combining several modules in one enclosure provides the following advantages:

• The combination of several systems enhances the functionality
• Outstanding software expansion options through suitable software interfaces
• Fewer plug connections increases reliability
• Less overall package space required for control units

Fig. 6: Front View Of CIC On E9x And E8x (Not Including E83, E85, E86)

CIC FRONT VIEW EXPLANATION CHART

1. Rotary/push button for (ON/OFF) and controlling the volume of audio system
2. Eject button for DVD/CD player
3. Favorite buttons 1-6
4. Slot for DVD/CD player
5. Station/track "forward-back" search button
6. MODE button (Radio, CD/DVD)
7. FM/AM button selects between the two frequency bands

Fig. 7: Rear View Of Car Information Computer

CIC REAR VIEW EXPLANATION CHART

1. LVDS signal for CID Connector color code: violet
2. Front View of the CIC on the E9x and E8x (not including E83, E85, E86)connection for glove compartment connector color code: beige
3. Ethernet connection Future expansions connector color code: pastel orange
4. MOST connector
5. 12-pin connector; right-hand chamber (Ethernet, TEL_AF, AUX_In)
6. 12-pin connector; left-hand chamber (video input signals - CSCC)
7. 16-pin connector (K-CAN, audio output AF; power supply, Rad-on signal)
8. GPS antenna signal Connector color code: blue
9. (Not for US)
10. (Not for US)
11. AM/FM tuner signal Connector color code: black

The transmission of picture data from the CCC to the CID was performed by means of an 8-wire LVDS line.

With the introduction of the Car Information Computer, the video signal is now transmitted through a 2-wire LVDS line.

The change in picture data transmission in the vehicle reflect the changes made in PC technology. While the printer was formerly connected to the PC via a parallel cable, data transmission now takes place using serial USB technology.

In the following graphics, 8-wire LVDS technology is compared to the new 2-wire LVDS technology:

8-wire LVDS

Transmission of video signals via 8-wire LVDS technology with CCC and CID.

(LVDS+ and LVDS- for each of the four signal lines and an additional synchronization line)

Fig. 8: 8-Wire LVDS Technology With CCC And CID

2-wire LVDS

Transmission of video signals via 2-wire LVDS technology with CIC and CID.

Fig. 9: 2-Wire LVDS Technology With CIC And CID

Signal transmission through this 2-wire LVDS line offers four distinct advantages:

• Higher data transfer rate
• Simplified wiring
• Runtime differences between the individual lines are avoided
• Serial 2-wire LVDS data transmission is now much more cost-effective than 8-wire LVDS technology

The main advantage of using serial 2-wire LVDS is the resulting high picture resolution.

A 4-core, shielded cable is used for the 2-wire LVDS technology. The cable consists of the four cores, LVDS+, LVDS-, 2x ground and shielding.

For Electromagnetic compatibility (EMC) reasons, the unused wire is also connected to ground.

In the illustration to the right, the advantages of both cores connected to ground are shown with the aid of field lines.

The capacitive interference of the signals is deflected to ground. The wires connected to ground form a defined potential and cannot act as antennas.

This ensures that additional interference is avoided.

Fig. 10: EMC Protection Using 2-Wire LVDS Technology

2-WIRE LVDS EXPLANATION CHART

1. Two signal-carrying cores, two cores connected to ground

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