atmega32c1 ATMEL Corporation, atmega32c1 Datasheet - Page 207

• Manufacturer Part Number: atmega32c1
• Description: Atmega32m1 Automotive 8-bit Avr Microcontroller With 32k/64k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

17.4.5
17.4.6
17.4.6.1
7647A–AVR–02/08
Enable / Disable
LIN Commands
Rx Header / LIN Abort Function
Table 17-1.
Setting the LENA bit in LINCR register enables the LIN/UART controller. To disable the
LIN/UART controller, LENA bit must be written to 0. No wait states are implemented, so, the dis-
able command is taken into account immediately.
Clearing the LCMD[2] bit in LINCR register enables LIN commands.
As shown in
register are available (c.f.
This function (or state) is mainly the withdrawal mode of the controller.
When the controller has to execute a master task, this state is the start point before enabling a
Tx Header command.
When the controller has only to execute slave tasks, LIN header detection/acquisition is enabled
as background function. At the end of such an acquisition (Rx Header function), automatically
the appropriate flags are set, and in LIN 1.3, the LINDLR register is set with the uncoded length
value.
This state is also the start point before enabling the Tx or the Rx Response command.
A running function (i.e. Tx Header, Tx or Rx Response) can be aborted by clearing LCMD[1..0]
bits in LINCR register. In this case, an abort flag - LABORT - in LINERR register will be set to
inform the other software tasks. No wait states are implemented, so, the abort command is taken
into account immediately.
Rx Header function is responsible for:
•
•
•
•
•
LENA
0
1
The BREAK field detection,
The hardware re-synchronization analyzing the SYNCH field,
The reception of the PROTECTED IDENTIFIER field, the parity control and the update of
the LINDLR register in case of LIN 1.3,
The starting of the Frame_Time_Out,
The checking of the LIN communication integrity.
LCMD[2]
Table 17-1 on page
x
0
1
LIN/UART Command List
LCMD[1]
x
0
1
0
1
0
1
Figure 17-5 on page
LCMD[0]
207, four functions controlled by the LCMD[1..0] bits of LINCR
x
0
1
0
1
0
0
1
1
Rx Header - LIN abort
Disable peripheral
206).
Rx Response
Tx Response
Byte transfer
Command
Full duplex
Tx Header
Rx Byte
Tx Byte
ATmega32/64/M1/C1
(LINDLR: read only register)
LCMD[2..0]=000 after Rx
LCMD[2..0]=000 after Tx
LCMD[2..0]=000 after Tx
no CRC, no Time out
LTXDL=LRXDL=0
LIN withdrawal
Comment
207