CAN Control Registers
1560
SPRUH22I – April 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
M3 Controller Area Network (CAN)
Figure 23-38. IF1 Message Control Register (CAN IF1MCTL) [offset = 0x10C]
31
16
Reserved
R-0
15
14
13
12
11
10
9
8
7
6
4
3
0
New
Dat
Msg
Lst
Int
Pnd
UMask
TxIE
RxIE
Rmt
En
Tx
Rqst
EoB
Reserved
DLC[3:0]
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R-0
R/WP-0
LEGEND: R = Read; WP = Protected Write (protected by Busy bit); -
n
= value after reset
Figure 23-39. IF2 Message Control Register (CAN IF2MCTL) [offset = 0x12C]
31
16
Reserved
R-0
15
14
13
12
11
10
9
8
7
6
4
3
0
New
Dat
Msg
Lst
Int
Pnd
UMask
TxIE
RxIE
Rmt
En
Tx
Rqst
EoB
Reserved
DLC[3:0]
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R/WP-
0
R-0
R/WP-0
LEGEND: R = Read; WP = Protected Write (protected by Busy bit); -
n
= value after reset
Table 23-21. IF1 and IF2 Message Control Registers Field Descriptions
Bit
Field
Value
Description
31-16
Reserved
Reserved
15
NewDat
New Data
0
No new data has been written into the data portion of this message object by the message handler
since the last time when this flag was cleared by the CPU.
1
The message handler or the CPU has written new data into the data portion of this message object.
14
MsgLst
Message Lost (only valid for message objects with direction = receive)
0
No message lost since the last time when this bit was reset by the CPU.
1
The message handler stored a new message into this object when NewDat was still set, so the
previous message has been overwritten.
13
IntPnd
Interrupt Pending
0
This message object is not the source of an interrupt.
1
This message object is the source of an interrupt. The Interrupt Identifier in the Interrupt Register
will point to this message object if there is no other interrupt source with higher priority.
12
UMask
Use Acceptance Mask
0
Mask ignored
1
Use Mask (Msk[28:0], MXtd, and MDir) for acceptance filtering
If the UMask bit is set to one, the message object's mask bits have to be programmed during
initialization of the message object before MsgVal is set to one.
11
TxIE
Transmit Interrupt Enable
0
IntPnd will not be triggered after the successful transmission of a frame.
1
IntPnd will be triggered after the successful transmission of a frame.
10
RxIE
Receive Interrupt Enable
0
IntPnd will not be triggered after the successful reception of a frame.
1
IntPnd will be triggered after the successful reception of a frame.
9
RmtEn
Remote Enable
0
At the reception of a remote frame, TxRqst is not changed.
1
At the reception of a remote frame, TxRqst is set.
Note: See
for details on the setup of RmtEn and UMask for remote frames.
