EP80579 Datasheet, PDF (1574/1916 Pages) Intel Corporation – Intel® EP80579 Integrated Processor Product Line

Intel^® EP80579 Integrated Processor
Note:
Figure 39-3. Extended CAN Data Frame
Extended Data Frame
Recessive level
Bus Idle _{1 11 1 1}
Dominant level
18 1 2 4
0...64
15 1 1 1 7
Start of Frame
Identifier
SRR Bit (R)
Arbitration Field
(without IDE bit)
IDE Bit (R)
Extended
Identifier
RTR Bit (D)
Control Field (2 reserved (D))
(plus IDE bit)
DLC
Data Field
CRC Field
CRC Sequence
CRC Delimiter
ACK Slot
Acknowledge Field
ACK Delimiter
End of Frame
Intermission
3 ^{Bus Idle}
To to use both Extended and Standard Frames on the same network, it is necessary to
split the 29 bit Extended identifier into one 11 bit (most significant) and one 18 bit
(least significant) section. By doing this, the IDE bit can remain in the same bit position
in both Standard and Extended Frames.
• Start of Frame: One dominant bit marks the beginning of both Data Frames and
Remote Frames. This is for hard synchronization with all nodes.
• Arbitration Field, consisting of:
— 11 bit identifier (most significant)
— SRR bit, recessive
— IDE bit, recessive to denote an Extended CAN Frame
— Extended Identifier, 18 bits
— 1 RTR bit. This bit is used to distinguish between a Data Frame(Dominant) and
a Remote Frame (Recessive).
• Control Field, consisting of:
— Two dominant bits
— Data Length Code, which is 4 bits wide
The remaining fields are similar to Standard Data Frame.
Intel^® EP80579 Integrated Processor Product Line Datasheet
1574
August 2009
Order Number: 320066-003US