CHAPTER 19 FCAN CONTROLLER (V850/SC3)
User’s Manual U15109EJ3V0UD
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19.10.4 Error frame
An error frame is output from a node in which an error has been detected.
Figure 19-23. Error Frame
<1>
R
D
<2>
<3>
6 bits
0 to 6 bits
8 bits
(<4>)
(<5>)
Interframe space or overload frame
Error delimiter
Error flag 2
Error flag 1
Error generation bit
Error frame
Remark
D: Dominant = 0
R: Recessive = 1
Table 19-22. Field Definitions of Error Frame
No.
Name
Bit Count
Definition
<1>
Error flag 1
6
Error active node: Consecutive output of 6 dominant-level bits.
Error passive node: Consecutive output of 6 recessive-level
bits.
When the other node outputs a dominant level during output of
the passive error flag, the passive error flag does not end until
6 same-level bits are detected consecutively.
<2>
Error flag 2
0 to 6
A node that receives error flag 1 is a node in which bit stuffing
errors are detected, after which error flag 2 is output.
<3>
Error delimiter
8
8 consecutive recessive-level bits are output.
If a dominant level bit is detected at the eighth bit, an overload
frame is transmitted starting at the next bit.
<4>
Error generation bit
–
Bit in which the error is detected.
This bit is output following the bit where the error occurred.
If the error is a CRC error, it is output following an ACK
delimiter.
<5>
Interframe space/overload
frame
–
An interframe space or overload frame starts from here.