LM3S2965_0711 Datasheet, PDF (436/574 Pages) List of Unclassifed Manufacturers – Microcontroller

Controller Area Network (CAN) Module
Register 8: CAN IF1 Command Request (CANIF1CRQ), offset 0x020
Register 9: CAN IF2 Command Request (CANIF2CRQ), offset 0x080
This register is used to start a transfer when its MNUM bit field is updated. Its Busy bit indicates that
the information is transferring from the CAN Interface Registers to the internal message RAM.
A message transfer is started as soon as there is a write of the message object number with the
MNUM bit. With this write operation, the Busy bit is automatically set to 1 to indicate that a transfer
is in progress. After a wait time of 3 to 6 CAN_CLK periods, the transfer between the interface
register and the message RAM completes, which then sets the Busy bit back to 0.
CAN IF1 Command Request (CANIF1CRQ)
CAN0 base: 0x4004.0000
CAN1 base: 0x4004.1000
Offset 0x020
Type RO, reset 0x0000.0001
31
30
29
28
27
26
25
Type RO
RO
RO
RO
RO
RO
RO
Reset
0
0
0
0
0
0
0
15
14
13
12
11
10
9
Busy
reserved
Type RO
RO
RO
RO
RO
RO
RO
Reset
0
0
0
0
0
0
0
24
23
reserved
RO
RO
0
0
8
7
RO
RO
0
0
22
21
20
19
18
17
16
RO
RO
RO
RO
RO
RO
RO
0
0
0
0
0
0
0
6
5
4
3
2
1
0
MNUM
RO
R/W
R/W
R/W
R/W
R/W
R/W
0
0
0
0
0
0
1
Bit/Field
31:16
15
14:6
5:0
Name
reserved
Busy
reserved
MNUM
Type
RO
RO
RO
R/W
Reset
0x0000
0x0
0x00
0x01
Description
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
Busy Flag
0: Reset when read/write action has finished.
1: Set when a write occurs to the message number in this register.
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
Message Number
Selects one of the 32 message objects in the message RAM for data
transfer. The message objects are numbered from 1 to 32.
Value
Description
0x00
0 is not a valid message number; it is interpreted as 0x20,
or object 32.
0x01-0x20 Indicates specified message object 1 to 32.
0x21-0x3F Not a valid message number; values are shifted and it is
interpreted as 0x01-0x1F.
436
November 30, 2007
Preliminary