Automotive open system architecture

IT in automobile
The name stands for…
Automotive open system architecture
Japan automotive software
platform architecture.
• An alliance of OEM manufacturers and
Tier 1 automotive suppliers
in August, 2002 and the partners
were joined soon afterwards by
Technology overview
ECU(engine control unit)
• The ECU uses closed-loop control, a control scheme
that monitors outputs of a system to control the inputs to
a system, managing the emissions and fuel economy of
the engine
• Gathering data from dozens of different sensors, the
ECU knows everything from the coolant temperature to
the amount of oxygen in the exhaust. With this data, it
performs millions of calculations each second, including
looking up values in tables, calculating the results of long
equations to decide on the best spark timing and
determining how long the fuel injector is open. The ECU
does all of this to ensure the lowest emissions and
best mileage.
Software component
A fundamental design concept of AUTOSAR
is the separation between:
• application
• infrastructure
“Atomic Software Component".
It cannot be distributed over several
• AUTOSAR Runtime Environment (RTE) acts as
a communication center for inter- and intra-ECU
information exchange
• RTE provides a communication abstraction to
AUTOSAR Software Components attached to it
by providing the same interface and services
whether inter-ECU communication channels are
used (such as CAN, LIN, FlexRay, MOST, etc.)
or communication stays intra-ECU.
Flexray ~communication system for automobile
• Fault-tolerant clock synchronization via a global
time base
• Collision-free bus access
• Guaranteed message latency
• Message oriented addressing via identifiers
• Scalable system fault-tolerance via the support
of either single or dual channels
Controller Area Network BUS
• A low speed CANbus may be employed to
operate window and seat controls.
• A high speed CANbus may be employed
for engine management or brake control.
Media Oriented Systems Transport
• POF( Plastic optical fiber)-based ~ largely
immune to electromagnetic interference.
• First deployed in 2001 BMW exclusive 7
series to achieve 5.6 Mb transmission rate.
AUTOSAR Basic Software
• Microcontroller Abstraction
Access to the hardware is routed through the
Microcontroller Abstraction layer (MCAL) to avoid direct
access to microcontroller registers from higher-level
MCAL is a hardware specific layer that ensures a
standard interface to the components of the Basic
Software. It manages the microcontroller peripherals and
provides the components of the Basic Software with
microcontroller independent values. MCAL implements
notification mechanisms to support the distribution of
commands, responses and information to different
• Currently, vendors in Taiwan can not get
involved in the standard.
• Most of products from Taiwan are