GF82.85-P-2030FAC Audio Mode, Function
GF82.85-P-2030FAC Audio Mode, Function
MODEL 203.7
- with CODE (527) COMAND APS with single DVD drive (with navigation)
MODEL 203.7 as of model year 09/YoM 08 model refinement package
Function requirements
- Circuit 30
- COMAND operating, display and controller unit (A40/3) is switched on
General
Audio consists of the following 2 subfunctions:
- Radio operation function sequence
- CD player mode function sequence
Operating instruction
The audio functions can be operated as follows:
- Directly at the COMAND operating, display and controller unit
- Via the multifunction steering wheel (MFL)
The volume can be adjusted separately for each audio source.
Radio operation function sequence
Radio operation consists of the following subfunctions:
- Function sequence for radio reception
- Function sequence for station tuning
- Function sequence for display information
- Function sequence for Radio Data System (RDS) (regional mode)
Function requirements for radio reception
- A receivable station is tuned in.
Function sequence for radio reception
A distinction must be made between the following 2 cases with regard to radio reception:
- Function sequence for radio reception, with code (810) Sound system
- Function sequence for radio reception, except code (810) Sound system
Function sequence for radio reception, with code (810) Sound system
The radio signals are received and output in the following way:
- Antennas in the rear window (receive FM and AM high frequency signals).
- Direct line
- Amplifier module 2, window antenna (A2/72) (filters and amplifies the radio frequency bands)
- Coaxial line
- COMAND operating, display and controller unit (demodulates the high frequency signals, i.e. it separates the useful information (audible frequencies) from the carrier signal (inaudible)).
- Media Oriented System Transport (MOST)
- Amplifier for sound system (N40/3)
- Direct line
- Speaker
The following speakers are installed in vehicles with code (810) Sound System: left front door speaker (H4/1), right front door speaker (H4/2), left rear door speaker (H4/5), right rear door speaker (H4/6), left front door speaker, mirror triangle (H4/23), right front door speaker, mirror triangle (H4/24), center cockpit speaker (centerfill) (H4/27), subwoofer speaker (H4/29), left rear surround speaker (H4/54), right rear surround speaker (H4/57)
Function sequence for radio reception, except code (810) Sound system
The radio signals are received and output in the following way:
- Antennas in the rear window (receive FM and AM high frequency signals).
- Direct line
- Amplifier module 2, window antenna (filters and amplifies the radio frequency bands)
- Coaxial line
- COMAND operating, display and controller unit (demodulates the high frequency signals, i.e. it separates the useful information (audible frequencies) from the carrier signal (inaudible) and amplifies it).
- Direct line
- Speaker
The following speakers are installed in vehicles without code (810) Sound System:
- Left front door speaker
- Right front door speaker
- Left rear door speaker
- Right rear door speaker
- Left front door mirror triangle speaker
- Right front door mirror triangle speaker
Function sequence for station tuning
A station can be tuned as follows:
- Tuning using station preset
- Tuning by program type list
- Tuning via frequency list
- Tuning by station search
- Tuning by station search on multifunction steering wheel
- Tuning by "Autostore" memory
- Tuning by "Scan" search (the stations of a waveband are played for 8 seconds)
- Tuning by means of manual adjustment
- Tuning by manual frequency input (via the 12-key panel of the COMAND operating, display and controller unit)
Function sequence for display information
As well as stations and transmission frequencies, the following radio functionality appears on the display of the COMAND operating, display and controller unit:
- Noise suppression
- Selection of RDS stations with a strong signal
- RDS information
RDS function requirements (regional operation)
- "Radio data system" function is activated.
- An RDS station is tuned in.
RDS function sequence (regional operation)
In addition to the radio program, many radio stations (e.g. FM) transmit additional inaudible digital information such as station name, type of programs (e.g. pop, culture, etc.) and traffic radio recognition. This information is evaluated by the COMAND operating, display and controller unit and shown on the display.
CD player mode function sequence
Audio CDs can be played using the COMAND operating, display and controller unit or using the CD player with changer (in glove compartment) (A2/6) (with code (819) 6-disk CD changer). The CD player with changer has a magazine for 6 CDs. The magazine is loaded centrally via an insertion slot. The system is operated via the keypad on the COMAND operating, display and controller unit.
Only 12 cm CDs may be inserted into the magazine of the CD player with changer.
CD player operation consists of the following subfunctions:
- Function sequence, transfer of control and audio signals
- Function sequence, playback of standard audio CDs
- Function sequence, playback of audio CDs in MP3 format
- Function sequence, assigning a title to an audio CD
Function sequence, transfer of control and audio signals
A distinction must be made between the following cases:
- Function sequence, transfer of control and audio signals, except code (819) 6-disk CD changer
- Function sequence, transfer of control signals, with code (819) 6-disk CD changer
- Function sequence, transfer of audio signals, with code (819) 6-disk CD changer
Function sequence, transfer of control and audio signals, except code (819) 6-disk CD changer
The control and audio signals are processed internally in the COMAND operating, display and controller unit.
Function sequence, transfer of control signals, with code (819) 6- disk CD changer
The control signals are transferred via the following route:
- COMAND operating, display and controller unit
- MOST
- CD player with changer
Function sequence, transfer of audio signals, with code (819) 6-disk CD changer
The audio signals are transferred via the following route:
- CD player with changer
- MOST
- COMAND operating, display and controller unit
Function requirements, playback of standard audio CDs
- Audio CD in DVD drive of the COMAND operating, display and controller unit or magazine with at least one audio CD in the insertion slot of the CD player with changer (with code (819) 6- disk CD changer)
Function sequence, playback of standard audio CDs
The operation of the CD player with changer (with code (819) 6-disk CD changer) or the DVD drive in the COMAND operating, display and controller unit is initiated in the "audio" menu by selecting the relevant function key. The following functions are available to the user:
- Select audio CD insertion slot in magazine (with code (819) 6-disk CD changer)
- Select audio CD (with code (819) 6-disk CD changer)
- Track selection
- "Search forwards" and "Search backwards"
- Current playback time of track or audio CD
- Programming function
When the end of the audio CD is reached, the DVD drive in the COMAND operating, display and controller unit stops playing, whereas the CD player with changer (with code (819) 6-disk CD changer) switches to the first track of the next available audio CD. The following functions are possible:
- Skip track: the music tracks are played for t = 8 seconds. At the end of the audio CD that is being played, the CD player with changer (with code (819) 6-disk CD changer) automatically switches to the mode last set.
- Random function - all tracks of an audio CD are played back according to the random principle. Once every track has been played, the next audio CD is loaded automatically (with code (819) 6-disk CD changer) and the random function continues. The random function is repeated until it is deactivated.
- Repeat function: either one track or all tracks of an audio CD are repeated. It is also possible to repeat all tracks of the audio CDs in the magazine (with code (819) 6-disk CD changer).
The following possibilities are available in the menu "Adjustments":
- Normal track function
- Repeat track
- Repeat audio CD
- Select a track sequence
The audio signals that are generated internally in the COMAND operating, display and controller unit or (with code (819) 6-disk CD changer) transferred to the COMAND operating, display and controller unit by the CD player with changer are output using the same method as radio signals: except code (810) Sound system direct to the relevant speakers, with code (810) Sound system via MOST to the sound system amplifier and from there to the relevant speakers via direct lines.
Function sequence, playback of audio CDs in MP3 format
The designation "MP3" is an abbreviation for MPEG 1 Audio Layer 3 and describes an audio compression standard that permits digital music signals to be compressed to approx. 8 % of the original data quantity. This is done with almost no audible difference to the original signal (audio CD). As well as conventional audio CDs, audio CDs in MP3 format can also be played in the DVD drive in the COMAND operating, display and controller unit and (with code (819) 6-disk CD changer) in the CD player with changer. While doing so, a conventional audio CD is emulated (simulated).
Function sequence, assigning a title to an audio CD
Each audio CD contains a permanently stored table of contents (TOC record). As a result, after a one-time user allocation of a title, it is possible to identify this CD title automatically, even if (with code (819) 6-disk CD changer) the audio CD is inserted into a different magazine. The TOC record additionally contains information concerning the number of titles on an audio CD and the audio CD's total playing time.
