574
32072H–AVR32–10/2012
AT32UC3A3
The minimum frame slot size is determined by TFrame_Maximum, and calculated below (all val-
ues in bit periods):
THeader_Nominal = 34
TFrame_Maximum = 1.4 x (THeader_Nominal + TResponse_Nominal + 1)
Note:
The term “+1” leads to an integer result for TFrame_Max (LIN Specification 1.3)
If the Checksum is sent (CHKDIS=0):
TResponse_Nominal = 10 x (NData + 1)
TFrame_Maximum = 1.4 x (34 + 10 x (DLC + 1 + 1) + 1)
TFrame_Maximum = 77 + 14 x DLC
If the Checksum is not sent (CHKDIS=1):
TResponse_Nominal = 10 x NData
TFrame_Maximum = 1.4 x (34 + 10 x (DLC + 1) + 1)
TFrame_Maximum = 63 + 14 x DLC
25.6.10.13
LIN Errors
This section describes the errors generated in LIN mode, and the coresponding error bits in
CSR. The error bits are cleared by writing a one to CR.RSTSTA. An interrupt request is gener-
ated if the corresponding bit in the Interrupt Mask Register (IMR) is set. This bit is set by writing
a one to the corresponding bit in the Interrupt Enable Register (IER).
Slave Not Responding Error (CSR.LINSNRE)
– This error is generated if no valid message appears within the TFrame_Maximum
time frame slot, while the USART is expecting a response from another node
(NACT=SUBSCRIBE).
Checksum Error (CSR.LINCE)
– This error is generated if the received checksum is wrong. This error can only be
generated if the checksum feature is enabled (CHKDIS=0).
Identifier Parity Error (CSR.LINIPE)
– This error is generated if the identifier parity is wrong. This error can only be
generated if parity is enabled (PARDIS=0).
Inconsistent Sync Field Error (CSR.LINISFE)
– This error is generated in slave mode if the Sync Field character received is not
0x55. Synchronization procedure is aborted.
Bit Error (CSR.LINBE)
– This error is generated if the value transmitted by the USART on Tx differs from the
value sampled on Rx. If a bit error is detected, the transmission is aborted at the
next byte border.
25.6.11
LIN Frame Handling
25.6.11.1
Master Node Configuration
Configure the baud rate by writing to BRGR.CD and BRGR.FP
Configure the frame transfer by writing to the LINMR fields NACT, PARDIS, CHKDIS,
CHKTYPE, DLM, FSDIS, and DLC
Select LIN mode and master node by writing 0xA to MR.MODE