TM4C1294KCPDT Datasheet, PDF (1387/1890 Pages) Texas Instruments – Tiva Microcontroller

Tiva^™ TM4C1294KCPDT Microcontroller
Register 8: CAN IF1 Command Request (CANIF1CRQ), offset 0x020
Register 9: CAN IF2 Command Request (CANIF2CRQ), offset 0x080
A message transfer is started as soon as there is a write of the message object number to the MNUM
field when the TXRQST bit in the CANIF1MCTL register is set. With this write operation, the BUSY
bit is automatically set to indicate that a transfer between the CAN Interface Registers and the
internal message RAM 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 clears the BUSY bit.
CAN IFn Command Request (CANIFnCRQ)
CAN0 base: 0x4004.0000
CAN1 base: 0x4004.1000
Offset 0x020
Type RW, reset 0x0000.0001
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
reserved
Type RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
BUSY
reserved
MNUM
Type RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RW
RW
RW
RW
RW
RW
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
Bit/Field
31:16
15
Name
reserved
BUSY
Type
RO
RO
Reset
0x0000
0
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
Value
0
1
Description
This bit is cleared when read/write action has finished.
This bit is set when a write occurs to the message
number in this register.
14:6
reserved
RO
0x00 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.
5:0
MNUM
RW
0x01 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
0x00
0x01-0x20
0x21-0x3F
Description
Reserved
0 is not a valid message number; it is interpreted
as 0x20, or object 32.
Message Number
Indicates specified message object 1 to 32.
Reserved
Not a valid message number; values are shifted and
it is interpreted as 0x01-0x1F.
June 18, 2014
Texas Instruments-Production Data
1387