Datasheet

281
7728G–AVR–06/10
ATtiny87/ATtiny167
6. LIN Break Delimitter
In SLAVE MODE, a BREAK field detection error can occur under following conditions.
The problem occurs if 2 conditions occur simultaneously:
a. The DOMINANT part of the BREAK is (N+0.5)*Tbit long with N=13, 14,15, ...
b. The RECESSIVE part of the BREAK (BREAK DELIMITER) is equal to 1*Tbit.
(see note below)
The BREAK_high is not detected, and the 2nd bit of the SYNC field is interpreted as the
BREAK DELIMITER.
The error is detected as a framing error on the first bits of the PID or on subsequent Data
or a Checksum error.
There is no error if BREAK_high is greater than 1*Tbit + 18%.
There is no problem in Master mode.
Note: LIN2.1 Protocol Specification paragraph 2.3.1.1 Break field says: “A break field is always gener-
ated by the master task(in the master node) and it shall be at least 13 nominal bit times of
dominant value, followed by a break delimiter, as shown in Figure 29-1. The break delimiter
shall be at least one nominal bit time long.”
Figure 29-1. The Break Field
Workaround
None
Frame
Break
Protected
identifier
field
Break
field
Data 1
Inter-byte space Inter-byte space
Break
delimiter
Data 2Data N ChecksumSync
field
Header Response
Response space