Network System - Audi Q7 2017 Manual

Network system

J794 is connected to J533 via the infotainment CAN bus in
all infotainment versions. The infotainment CAN bus is a
high-speed bus with a max. data transfer rate of 500 kbit/s.
The following control units may also be connected to the
infotainment CAN depending on trim level:
• Instrument Cluster Control Module J285.
• Windshield Projection Head up Display Control
Module J898.
• Selector Lever Sensor System Control Module J587.
Front Information Display Control Head J685 and Multime-
dia System Control Head E380 are connected to J794 via
the Modular Infotainment Platform (MIB) CAN bus. It has
a speed of 500 kbit/s.
The MOST bus is a MOST 150 with a data transfer rate of
150 Mbit/s. J794 acts both as the system master and
diagnostics master for the MOST bus.
Due to the combination of infotainment CAN bus and MOST
bus, an open circuit in the MOST bus will not result in total
failure of the MMI. This means that all functions executed
directly in J794 are still available. However, audio output
via an external amplifier would no longer be possible.
Image transfer
All image information which appears on Front Information
Display Control Head J685 is sent from J794 via LVDS lines.
The displays for J285 are transferred from J794 as follows:
• LVDS:
Only large navigation map and detailed intersection
maps.
• MOST bus:
All other content, such as list menus or cover art.
The image information from the DVD change is transmitted
in the form of mpeg4 files via the MOST bus to J794. J794
then decodes this data.
Image information from the Peripheral Camera Control
Module J928 (TopView) is transmitted toJ794 via LVDS
lines.
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Infotainment topology
Driver Volume Control
E67
Multimedia System
Control Head
E380
Front Information
Display Control Head
J685
Wire colors:
Modular Infotainment Platform (MIB) CAN
LIN bus
Extended CAN
Infotainment CAN bus
MOST bus
LVDS
"OR" configuration