Datasheet

Table Of Contents
Figure 34-13. LIN Frame Format
Header
Slave response
Break Sync ID
1-8 Data bytes Checksum
TxD
RxD
Using the LIN command field (CTRLB.LINCMD), the complete header can be automatically transmitted,
or software can control transmission of the various header components.
When CTRLB.LINCMD=0x1, software controls transmission of the LIN header. In this case, software
uses the following sequence.
CTRLB.LINCMD is written to 0x1.
DATA register written to 0x00. This triggers transmission of the break field by hardware. Note that
writing the DATA register with any other value will also result in the transmission of the break field by
hardware.
DATA register written to 0x55. The 0x55 value (sync) is transmitted.
DATA register written to the identifier. The identifier is transmitted.
When CTRLB.LINCMD=0x2, hardware controls transmission of the LIN header. In this case, software
uses the following sequence.
CTRLB.LINCMD is written to 0x2.
DATA register written to the identifier. This triggers transmission of the complete header by hardware.
First the break field is transmitted. Next, the sync field is transmitted, and finally the identifier is
transmitted.
In LIN master mode, the length of the break field is programmable using the break length field
(CTRLC.BRKLEN). When the LIN header command is used (CTRLB.LINCMD=0x2), the delay between
the break and sync fields, in addition to the delay between the sync and ID fields are configurable using
the header delay field (CTRLC.HDRDLY). When manual transmission is used (CTRLB.LINCMD=0x1),
software controls the delay between break and sync.
Figure 34-14. LIN Header Generation
Configurable
Break Field Length
Sync Field Identifier Field
LIN Header
Configurable delay using CTRLC.HDRDLY
After header transmission is complete, the slave responds with 1-8 data bytes plus checksum.
34.6.3.6 RS485
RS485 is available with the following configuration:
USART frame format (CTRLA.FORM = 0x00 or 0x01)
RS485 pinout (CTRLA.TXPO=0x3).
The RS485 feature enables control of an external line driver as shown in the figure below. While
operating in RS485 mode, the transmit enable pin (TE) is driven high when the transmitter is active.
SAM D5x/E5x Family Data Sheet
SERCOM USART - SERCOM Synchronous and Asyn...
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Datasheet
DS60001507E-page 934