MEGA128CAN Datasheet, PDF (254/413 Pages) ATMEL Corporation – Microcontroller WITH 128K BYTES OF ISP FLASH AND CAN CONTROLLER

CAN Highest Priority MOb
Register - CANHPMOB
CAN Page MOb Register -
CANPAGE
MOb Registers
CAN MOb Status Register -
CANSTMOB
Bit
Read/Write
Initial Value
7
6
5
4
HPMOB3 HPMOB2 HPMOB1 HPMOB0
R
R
R
R
1
1
1
1
3
CGP3
R/W
0
2
CGP2
R/W
0
1
CGP1
R/W
0
0
CGP0
R/W
0
CANHPMOB
• Bit 7:4 – HPMOB3:0: Highest Priority MOb Number
MOb having the highest priority in CANSIT registers.
If CANSIT = 0 (no MOb), the return value is 0xF.
• 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).
Bit
Read/Write
Initial Value
7
6
5
4
MOBNB3 MOBNB2 MOBNB1 MOBNB0
R/W
R/W
R/W
R/W
0
0
0
0
3
AINC
R/W
0
2
INDX2
R/W
0
1
INDX1
R/W
0
0
INDX0
R/W
0
CANPAGE
• Bit 7:4 – MOBNB3:0: MOb Number
Selection of the MOb number, the available numbers are from 0 to 14.
• 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.
The MOb registers has no initial (default) value after RESET.
Bit
Read/Write
Initial Value
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
• 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 soft-
ware routine on the whole CANSTMOB register.
The communication enabled by transmission is completed. 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.
254 AT90CAN128
4250E–CAN–12/04