DCAN Control Registers
1102
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Controller Area Network (DCAN) Module
23.17.20 IF1/IF2 Mask Registers (DCAN IF1MSK, DCAN IF2MSK)
The bits of the IF1/IF2 Mask Registers mirror the mask bits of a message object. The function of the
relevant message objects bits is described in
.
NOTE:
While the Busy bit in the IF1/IF2 Command Register is 1, IF1/IF2 Register Set is write
protected.
Figure 23-54. IF1 Mask Register (DCAN IF1MSK) [offset = 104h]
31
30
29
28
16
MXtd
MDir
Rsvd
Msk[28:16]
R/WP-1
R/WP-1
R-1
R/WP-1FFFh
15
0
Msk[15:0]
R/WP-FFFFh
LEGEND: R/W = Read/Write; R = Read only; WP = Protected Write (protected by Busy bit); -
n
= value after reset
Figure 23-55. IF2 Mask Register (DCAN IF2MSK) [offset = 124h]
31
30
29
28
16
MXtd
MDir
Rsvd
Msk[28:16]
R/WP-1
R/WP-1
R-1
R/WP-1FFFh
15
0
Msk[15:0]
R/WP-FFFFh
LEGEND: R/W = Read/Write; R = Read only; WP = Protected Write (protected by Busy bit); -
n
= value after reset
Table 23-22. IF1/IF2 Mask Register Field Descriptions
Bit
Field
Value
Description
31
MXtd
Mask Extended Identifier
0
The extended identifier bit (IDE) has no effect on the acceptance filtering.
1
The extended identifier bit (IDE) is used for acceptance filtering.
When 11-bit ("standard") identifiers are used for a message object, the identifiers of received Data
Frames are written into bits ID[28:18]. For acceptance filtering, only these bits with mask bits
Msk[28:18] are considered.
30
MDir
Mask Message Direction
0
The message direction bit (Dir) has no effect on the acceptance filtering.
1
The message direction bit (Dir) is used for acceptance filtering.
29
Reserved
1
This bit is always read as 1. Writes have no effect.
28-0
Msk[
n
]
Identifier Mask
0
The corresponding bit in the identifier of the message object is not used for acceptance filtering
(don't care).
1
The corresponding bit in the identifier of the message object is used for acceptance filtering.