
CAN FD v2.0
45
PG223 December 5, 2018
Chapter 2:
Product Specification
TB*-ID Register (Address 0x0100, 0x0148 …)
0x0A08
M1/AFMR1
Read, Write
See
ID Filter Mask pair 1
0x0A0C
F1/AFIR1
Read, Write
0x0A10-
0x0AFC
M2,
F2-M31,
F31
Read, Write
ID Filter Mask pairs 2 to 31
Notes:
1. Read from uninitialized memory location might return X or invalid data. Asserting a soft or hard reset does not
clear block RAM locations.
2. Each TB is linked to a bit in TRR register. Core access TB elements inside TX block RAM only if respective TRR bit is
set. After setting TRR bit, Host should not access the TX message elements until TRR is cleared by the core to avoid
memory collision issues.
Table 2-31:
TB ID Register
Bits
Name
Control/
Status
Default
Value
Description
31:21
ID[28:18]
Control
N/A
Standard Message ID.
The Identifier portion for a Standard Frame is 11 bits.
These bits indicate the Standard Frame ID. This field is
valid for both CAN and CAN FD Standard and Extended
Frames.
20
SRR/RTR/RRS
Control
N/A
Substitute Remote Transmission Request.
For Extended CAN frames and Extended CAN FD frame
this bit is transmitted at SRR position of the respective
frame and must be set as 1.
For Standard CAN FD frame this bit is transmitted at RRS
position of the frame and must be set as 0.
This bit differentiates between standard CAN data frames
and standard CAN remote frames as the following:
• 1 = Indicates that the message frame is a Standard
Remote CAN Frame.
• 0 = Indicates that the message frame is a Standard
Data CAN Frame.
Note:
There are no CAN FD remote frames.
19
IDE
Control
N/A
Identifier Extension
This bit differentiates between frames using the Standard
Identifier and those using the Extended Identifier.
Valid for both CAN and CAN FD Standard and Extended
Frames.
• 1 = Indicates the use of an Extended Message
Identifier.
• 0 = Indicates the use of a Standard Message Identifier.
Table 2-30:
CAN FD TX Message Space
(Cont’d)
Start
Address
Name
Access
Description
Notes