• Bit 3:0 – CGP3:0: CAN General Purpose Bits
These bits can be pre-programmed to match with the wanted configuration of the CANPAGE
register (i.e., AINC and INDX2:0 setting).
16.10.17 CAN Page MOb Register - CANPAGE
Bit
7
6
5
4
3
2
1
0
MOBNB3 MOBNB2 MOBNB1 MOBNB0
AINC
R/W
0
INDX2
R/W
0
INDX1
R/W
0
INDX0
R/W
0
CANPAGE
Read/Write
Initial Value
R/W
0
R/W
0
R/W
0
R/W
0
• Bit 7:4 – MOBNB3:0: MOb Number
Selection of the MOb number, the available numbers are from 0 to 5.
Note: MOBNB3 always must be written to zero for compatibility with all AVR CAN devices.
• Bit 3 – AINC: Auto Increment of the FIFO CAN Data Buffer Index (Active Low)
– 0 - auto increment of the index (default value).
– 1- no auto increment of the index.
• Bit 2:0 – INDX2:0: FIFO CAN Data Buffer Index
Byte location of the CAN data byte into the FIFO for the defined MOb.
16.11 MOb Registers
The MOb registers has no initial (default) value after RESET.
16.11.1 CAN MOb Status Register - CANSTMOB
Bit
7
DLCW
R/W
-
6
TXOK
R/W
-
5
RXOK
R/W
-
4
BERR
R/W
-
3
SERR
R/W
-
2
CERR
R/W
-
1
FERR
R/W
-
0
AERR
R/W
-
CANSTMOB
Read/Write
Initial Value
• Bit 7 – DLCW: Data Length Code Warning
The incoming message does not have the DLC expected. Whatever the frame type, the DLC
field of the CANCDMOB register is updated by the received DLC.
• Bit 6 – TXOK: Transmit OK
This flag can generate an interrupt. It must be cleared using a read-modify-write software routine
on the whole CANSTMOB register.
The communication enabled by transmission is completed. TxOK rises at the end of EOF field.
When the controller is ready to send a frame, if two or more message objects are enabled as
producers, the lower MOb index (0 to 14) is supplied first.
• Bit 5 – RXOK: Receive OK
This flag can generate an interrupt. It must be cleared using a read-modify-write software routine
on the whole CANSTMOB register.
The communication enabled by reception is completed. RxOK rises at the end of the 6th bit of
EOF field. In case of two or more message object reception hits, the lower MOb index (0 to 14)
is updated first.
196
ATmega16/32/64/M1/C1
7647F–AVR–04/09
ATMEL [ ATMEL ]
