Atmel ARM-Based Evaluation Kit AT91SAM9N12-EK AT91SAM9N12-EK Data Sheet
Product codes
AT91SAM9N12-EK
795
SAM9N12/SAM9CN11/SAM9CN12 [DATASHEET]
11063K–ATARM–05-Nov-13
Figure 40-47. Master Node Configuration, NACT = IGNORE
Slave Node Configuration
Write TXEN and RXEN in US_CR to enable both the transmitter and the receiver.
Write USART_MODE in US_MR to select the LIN mode and the Slave Node configuration.
Write CD and FP in US_BRGR to configure the baud rate.
Wait until LINID in US_CSR rises
Check LINISFE and LINPE errors
Read IDCHR in US_RHR
Write NACT, PARDIS, CHKDIS, CHKTYPE, DLCM and DLC in US_LINMR to configure the frame transfer.
IMPORTANT: If the NACT configuration for this frame is PUBLISH, the US_LINMR must be written with NACT =
PUBLISH even if this field is already correctly configured, in order to set the TXREADY flag and the corresponding write
transfer request.
PUBLISH even if this field is already correctly configured, in order to set the TXREADY flag and the corresponding write
transfer request.
What comes next depends on the NACT configuration:
Case 1: NACT = PUBLISH, the LIN controller sends the response
Wait until TXRDY in US_CSR rises
Write TCHR in US_THR to send a byte
If all the data have not been written, redo the two previous steps
Wait until LINTC in US_CSR rises
Check the LIN errors
Case 2: NACT = SUBSCRIBE, the USART receives the response
Wait until RXRDY in US_CSR rises
Read RCHR in US_RHR
If all the data have not been read, redo the two previous steps
Wait until LINTC in US_CSR rises
Check the LIN errors
Case 3: NACT = IGNORE, the USART is not concerned by the response
Wait until LINTC in US_CSR rises
Check the LIN errors
TXRDY
Write
US_LINIR
RXRDY
LINTC
Break
Synch
Protected
Identifier
Data 1
Data N
Checksum
Data N-1
Header
Inter-
frame
space
Response
space
Frame
Frame slot = TFrame_Maximum
Response
Data3
FSDIS=1
FSDIS=0