Grundlagen FlexRay - Institut für Automatisierungs- und ...

Grundlagen FlexRay BasicsV 1.1 8
FIBEX
Frame
FTDMA
Header
Host
Jitter
Knoten/Node
Layer
Macrotick
Microtick
Minislot
Null Frame
Payload
PDU
Slot
Startup Frame
Startup Slot
Data format based on XML, which defines the entire FlexRay network
A Frame is a basic structure, which is used to transmit data via the
FlexRay network. A frame consists of a header, payload, and trailer
segment.
Access method, which assigns a node a time window, in which the
node has exclusive resource access
First part of a frame, which includes information on the frame
The host contains the user software of an ECU
A derivation in time towards the synchronous clock
Active functional unit, which can send and receive messages
Architectural layer, which describes the functions and tasks of a
component within that layer
A cycle is globaly divided into macrotics. Macrotics are generated out
of the local microtics. The duration of a macrotic is adjusted dring the
synchronization.
The duration of a microtic is derived from the local osciliator of a node.
They are used for bus synchronization.
These slots divide the dynamic segment into up to 7986 parts. They can
be combined into a dynamic slot.
A frame which does not include any data for the receiver is called null
frame. It is identified by a bit in the header, and all data bytes are set to
Data_0
This segment contains all payload data of a frame.
PDUs are bus-independent units of data, consisting of payload and
control data.
See Communication Slot.
Startup frames are FlexRay frames which are identified by the Startup
Frame Indicator bit in the header. They are sent for 8 cycles at the start
of the synchronization process. A startup frame always is a sync frame
as well.
Communication slot in which a startup frame is sent.
Bäurle 12.10.2012