Datasheet

604
32117D–AVR-01/12
AT32UC3C
25.6.9.6 Header Transmission (Master Node Configuration)
All the LIN Frames start with a header which is sent by the master node and consists of a Synch
Break Field, Synch Field and Identifier Field.
So in Master node configuration, the frame handling starts with the sending of the header.
The header is transmitted as soon as the identifier is written in the LIN Identifier register (LINIR).
At this moment the flag TXRDY falls.
The Break Field, the Synch Field and the Identifier Field are sent automatically one after the
other.
The Break Field consists of 13 dominant bits and 1 recessive bit, the Synch Field is the charac-
ter 0x55 and the Identifier corresponds to the character written in the LIN Identifier Register
(LINIR). The Identifier parity bits can be automatically computed and sent (see Section
25.6.9.9).
The bit TXRDY is set when the identifier character is transferred into the Shift Register of the
transmitter.
Figure 25-39. Header Transmission
TXD
Baud Rate
Clock
Start
Bit
Write
LINIR
10101010
TXRDY
Stop
Bit
Start
Bit
ID0 ID1 ID2 ID3 ID4 ID5 ID6 ID7Break Field
13 dominant bits (at 0)
Stop
Bit
Break
Delimiter
1 recessive bit
(at 1)
Synch Byte = 0x55
LINIR
ID