![](http://datasheet.mmic.net.cn/30000/M30956FKTGP_datasheet_2359453/M30956FKTGP_399.png)
22.1.23 CANi Acceptance Filter Support Register (CiAFS Register) (i = 0, 1)
Figure 22.36
C0AFS and C1AFS Registers
The CiAFS register enables prompt performance of a table search to determine a validity of the received ID.
This function is for standard-formatted ID only.
Symbol
Address
After Reset(1)
RW
CANi Acceptance Filter Support Register (i = 0,1)
C0AFS
C1AFS
0245h - 0244h
0255h - 0254h
0100h
Function
NOTE:
1. The value is obtained by setting the SLEEP bit in the CiSLPR register to 1 (sleep mode exited) after reset and supplying
the clock to the CAN module.
b7
b0
Data to determine the received ID is generated
SID5
SID4
SID3
SID2
SID1
SID10
SID9
SID8
SID7
SID6
SID0
CSID0
CSID7 CSID6 CSID5 CSID4 CSID3 CSID2
SID10
SID9
SID8
SID7
SID6
SID5
SID4
SID3
CSID1
Write
Read
006h
0
005h
0
004h
0
003h
0
002h
0
001h
1
000h
0
007h
0
00Eh
0
00Dh
0
00Ch
0
00Bh
0
00Ah
0
009h
0
008h
0
00Fh
1
Data for a data table search is generated
from the received ID in standard format.
The table search with this data determines
whether or not the received ID is valid.
3-8 decoding
b15
b0
b8
b7
6F6h
0
6F5h
0
6F4h
0
6F3h
1
6F2h
0
6F1h
0
6F0h
0
6F7h
0
7F6h
0
7F5h
0
7F4h
0
7F3h
0
7F2h
0
7F1h
0
7F0h
1
7F7h
0
7FEh
0
7FDh
1
7FCh
0
7FBh
0
7FAh
0
7F9h
0
7F8h
0
7FFh
0
Bit search information
Address search information
Top + 00h
Top + 01h
Top + DEh
Top + FEh
Top + FFh
When the received ID is 6F3h
b15
b0
b8
b7
Write to the
CiAFS register
SID5
001100
1
00011011
1
SID4 SID3 SID2 SID1 SID0
SID10 SID9 SID8 SID7 SID6
6
F
3
11
011
11
0
1
0
D
E
3
Received ID
Divide it to
8 bits and 3 bits
8 bits
3 bits
000010
0
11011110
0
08h
D
E
Bit search information
Address search information
Bit search information
b7
b0
3 low-order bits of
received ID
01h
02h
04h
08h
10h
20h
40h
80h
0 0 0 0 0 0 0 1
0 0 0 0 0 0 1 0
0 0 0 0 0 1 0 0
0 0 0 0 1 0 0 0
0 0 0 1 0 0 0 0
0 0 1 0 0 0 0 0
0 1 0 0 0 0 0 0
1 0 0 0 0 0 0 0
0h
1h
2h
3h
4h
5h
6h
7h
Because the value of
the 3 bits is 3, b3 in the
left table is 1. (If the
value of the 3 bits is 4,
b4 in the left table is 1.)
Read from the
CiAFS register
b15
b8
b7
b6
b5
b4
b3
b2
b1
b0
SID10
SID0
b15
b0
b8
b7
i = 0, 1
Setting Range
0000h to FFFFh