ETAS
Hardware description
ES583.1 - User's Guide
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3.7.2
Bus termination resistor
The FlexRay specification allows the design of different bus topologies, such as
passive bus, passive star or active star.
Each of the topologies requires a corresponding bus termination. The FlexRay
termination selected by ETAS in the context of the FlexRay specification mea
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sures 100 ohm. To support the design in FlexRay networks, ETAS offers Flex
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Ray cables and matching FlexRay terminations. The terminations must be
connected to the cable or the plug.
3.7.3
Synchronization nodes
After the start of a FlexRay network, the local clock generators of all nodes of
the network must be synchronized. Prerequisites for the synchronization pro
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cess are at least two nodes that can send sync frames (synchronization
nodes). The other nodes of the network synchronize themselves by analyzing
the occurrence of the sync frame and adjusting their local clock generator.
The FlexRay interface of the ES583.1 is equipped with an additional internal
synchronization node. The synchronization node can take over only synchroni
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zation functions and is internally connected with the FlexRay channels FLX1
and FLX2.
If this synchronization node sends Start-up/Sync messages as the second
node of the FlexRay network, then FlexRay networks in which no other nodes
with synchronization module exist can be started and synchronized with a sin
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gle ES583.1 module.
Application examples
• Testing/starting up FlexRay ECUs outside of FlexRay networks
• Flashing ECUs via FlexRay
3.8
Firmware update
The firmware of the ES583.1 can be updated by the user so that future versions
of the module can also be used. The firmware update is done with the help of
the service software "Hardware Service Pack" (HSP) from the connected PC.
NOTE
During a firmware update, the USB connection to the PC must not be discon
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nected!
