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11 mob registers, 1 canstmob – can mob status register – Rainbow Electronics ATmega64M1 User Manual

Page 192

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192

8209A–AVR–08/09

ATmega16M1/32M1/64M1

• Bit 3:0 – CGP[3:0]: 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).

20.10.17 CANPAGE – CAN Page MOb Register

• 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 – INDX[2:0]: FIFO CAN Data Buffer Index

Byte location of the CAN data byte into the FIFO for the defined MOb.

20.11 MOb Registers

The MOb registers has no initial (default) value after RESET.

20.11.1

CANSTMOB – CAN MOb Status Register

• 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 6

th

bit of

EOF field. In case of two or more message object reception hits, the lower MOb index (0 to 14)
is updated first.

Bit

7

6

5

4

3

2

1

0

MOBNB3

MOBNB2

MOBNB1

MOBNB0

AINC

INDX2

INDX1

INDX0

CANPAGE

Read/Write

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

Initial Value

0

0

0

0

0

0

0

0

Bit

7

6

5

4

3

2

1

0

DLCW

TXOK

RXOK

BERR

SERR

CERR

FERR

AERR

CANSTMOB

Read/Write

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

Initial Value

-

-

-

-

-

-

-

-