GF82.85-P-2030FLJ Audio Mode, Function
GF82.85-P-2030FLJ Audio Mode, Function
- with CODE (527) COMAND APS with single DVD drive (with navigation system)
- with CODE (498) Japan version
Function requirements
^ Status circuit 30g ON
Audio functions can be selected, activated and adjusted with the following components:
- Left multifunction steering wheel button group (S110) or right multifunction steering wheel button group (S111)
- Audio/COMAND control panel (A40/9)
- Function keys of the COMAND controller unit (A40/3)
General
On vehicles with code (810) Sound system, the audio signals are sent by the COMAND controller unit via Media Oriented System Transport (MOST) to the sound system amplifier control unit (N40/3), where they are amplified.
The audio output takes place directly over the following speakers:
- Center dashboard speaker (H4/27)
- Left rear surround speaker (H4/54)
- Right rear surround speaker (H4/55) (with model 212.2)
- Right rear surround speaker (H4/57) (with model 212.0)
- Left front door sound system tweeter (H4/68)
- Right front door sound system tweeter (H4/69)
- Left rear door sound system tweeter (H4/70)
- Right rear door sound system tweeter (H4/71)
- Left front door sound system midrange and bass speakers (H4/72)
- Right front door sound system midrange and bass speakers (H4/73)
- Left rear door sound system midrange speaker (H4/80)
- Right rear door sound system midrange speaker (H4/81)
For the bass speaker (H4/17) (model 212.0) or for the bass speaker (H4/29) (model 212.2), the audio signal is routed from the COMAND controller unit to the sound system amplifier control unit via MOST and from there to the bass speaker via the rear bass speaker amplifier (N40/9) using direct lines.
On vehicles without code (810) Sound system, the audio signals are output over direct lines by the COMAND controller unit to the following speakers:
- Left front door speaker (H4/1)
- Left front door tweeter (H4/1h1)
- Right front door speaker (H4/2)
- Right front door tweeter (H4/2h1)
- Left rear door speaker (H4/3)
- Left rear door tweeter (H4/3h1)
- Right rear door speaker (H4/4)
- Right rear door tweeter (H4/4h1)
Function sequence for audio mode
The audio mode consists of the following component functions:
^ Function sequence for radio mode (FM/AM)
^ Function sequence for audio DVD/CD
^ Function sequence for Music Register (hard disk or memory card)
^ Function sequence for media interface
^ Function sequence for Bluetooth(R) audio (as of 1.6.2010)
Function sequence for radio mode (FM/AM)
The antennas in the rear window receive high frequency (HF) signals for the FM and AM (MW) radio frequency bands.
The following useful signals relevant for the radio reception are modulated onto these HF signals:
- Music signals
- Speech signals
- Data signals (e.g. Vehicle Information and Communication System (VICS) signals on the current traffic information)
The HF signals are received by the antenna structure in the rear window and sent over direct lines to the FM 1, AM, CL [ZV], and KEYLESS-GO antenna amplifier (A2/18), and to the FM 2 and DAB antenna amplifier (A2/19).
These two amplifiers filter the frequencies of the radio frequency bands out of the received HF signals and amplify them. The amplified signals are then sent via coaxial lines to the tuner integrated in the COMAND controller unit and demodulated.
The radio mode function sequence consists of the following component functions:
^ AM tuner (MW) function
^ FM dual tuner with phase diversity (FM)
AM tuner (MW) function
For the MW radio frequency band, the useful signals are broadcast using amplitude modulation. To separate the useful signals (audible frequencies) from the carrier signal (inaudible), the AM tuner integrated into the COMAND controller unit, demodulates the signals.
FM dual tuner with phase diversity (FM)
For the FM radio frequency band, the useful signals are transmitted using frequency modulation. These signals are demodulated by the FM tuner integrated into the COMAND controller unit. In other words, it also separates the useful signals (audible frequencies from the carrier signal (inaudible).
VICS signals are demodulated by a separate FM tuner.
Function sequence for audio DVD/CD
A single DVD drive is integrated into the COMAND controller unit. The audio DVD/CD function enables audio DVDs or audio CDs (including MP3 format) to be played. User guidance for controlling DVD/CD functionality and displaying supplemental information is carried out in the audio/COMAND display (A40/8). The data exchange for controlling the DVD/CD functionality (e.g. track selection) between the COMAND controller unit and the Audio/ COMAND display takes place through the telematics CAN (CAN A). The signals for displaying the menus and the supplemental information (e.g. track) are sent over a low voltage differential signaling (LVDS) line.
Function sequence for Music Register (hard disk or memory card)
On the integrated hard drive in the COMAND controller unit, files (in the MP3 format) from a CD/DVD or a Personal Computer Memory Card International Association (PCMCIA) card can be stored and then called up again as and when required.
Function sequence for media interface
The audio signals and data of a connected, portable terminal (e.g. MP3 player) are sent over the following path to the COMAND controller unit:
- Adapter cable
- Media interface electrical connector (X18/70)
- Media interface control unit (N125/1)
- MOST
Selection of the "Media interface" menu item as well as the specific submenu item (Playlists, Artists, Albums, Genres or Audio books) enables the audio data to be shown on the Audio/COMAND display.
The "Media interface" menu item and the specific submenu item can be selected using one of the following controls:
- Function keys of the COMAND controller unit
- Audio/COMAND control panel
- Left multifunction steering wheel button group and right multifunction steering wheel button group
Function sequence for Bluetooth(R) audio (as of 1.6.2010)
Via the Bluetooth antenna (A2/91), the COMAND controller unit can receive Bluetooth(R) audio signals from external devices. Bluetooth(R) audio is divided into the following subfunctions:
^ Search for devices and authorization
^ Connection and reconnection
^ Meta data and display of information
Search for devices and authorization
The same options exist for the authorization of a Bluetooth(R) audio source as are available for telephony:
- Search via the device list or
- External authorization
The device lists are set up the same for Bluetooth(R) audio and telephony. In the respective list, only those devices that support the corresponding Bluetooth(R) profile of the respective function are found or displayed during a search. During telephony, the hands- free profile (HFP) is used.
With Bluetooth(R) audio, the Audio/Video Remote Control Profile (AVRCP) and Advanced Audio Distribution Profile (A2DP) are used. If a device supports both functions, it is shown in both lists following authorization.
Connection and reconnection
An authorized device can be connected by means of selection in the corresponding list. If a device is connected that supports both HFP and AVRCP and A2DP, all profiles are connected. That means that the device is now a telephone and at the same time a source for Bluetooth(R) audio. On most devices, it is necessary to start the player on the telephone so that it can then be controlled via the COMAND controller unit.
When starting, the COMAND controller unit proceeds with the following strategy: First a check is performed as to whether an authorized telephone is inserted in the mobile phone cradle (A34/15) (with code (386) Comfort telephony). If this is the case, the COMAND controller unit connects to the telephone and assumes the comfort telephony status.
If a mobile phone cradle (with code (386) Comfort telephony) is present but no telephone is inserted, a prompt appears after 2 min as to whether a switchover to basic telephony is desired. With "No", the system remains in the comfort telephony status. If no mobile phone cradle is present, the COMAND controller unit searches for the last two telephones. If one of these devices is found, the COMAND controller unit connects to this device. If this device also supports AVRCP and A2DP, these profiles are also connected. If a device is connected that only supports HFP and it is changed to the Bluetooth(R) audio application, "No Bluetooth audio device connected" is shown on the Audio/COMAND display if the corresponding audio sources are shown in the device list.
With the comfort telephony status, the connected device is always treated as if it only supports HFP.
If no Bluetooth(R) audio source is shown in the device list, "No Bluetooth audio device authorized" is shown on the Audio/ COMAND display and the selection option "Connect last device" is not shown in the menu.
If a Bluetooth(R) audio source is shown in the device list, the last Bluetooth(R) audio source used can be connected via "Connect last device". However, the connection to the current telephone is interrupted here.
The search process with "Connect last device" can only be interrupted by changing to telephony. Otherwise, the search is continued in the background.
If a device is connected that only supports AVRCP and A2DP and a change to telephony is then made, the connection to the device is disconnected and the COMAND controller unit begins the search for the last two telephones.
Meta data and display of information
The display of information for Bluetooth(R) audio depends on the respective device used. If this supports AVRCP 1.0, "Audio streaming" is exclusively shown on the Audio/COMAND display and in the instrument cluster (A1).
As of AVRCP 1.3, the track, album and artist are shown. In addition, the currently played time of the track can also be conveyed. Furthermore, there is the option of changing between the normal track sequence and shuffle.
It is possible to jump to the next or the previous track using the left multifunction steering wheel button group.
Notes on supported devices for Bluetooth(R) audio can be found.
