GD32F403xx User Manual
609
Figure 22-5. 32-bit filter
FDATA[31:21]
FDATA[20:3]
FDATA[2:0]
SFID[10:0]
EFID[17:0]
FF
FT
0
16-bit: SFID [10:0], FT, FF and EFID[17:15] bits. As is shown in
.
Figure 22-6. 16-bit filter
FDATA[31:21]
FDATA[20:16]
SFID[10:0]
FT
FF EFID[17:15]
FDATA[15:5]
FDATA[4:0]
SFID[10:0]
FT
FF EFID[17:15]
Mask mode
For the Identif ier of a data f rame to be filtered, the mask mode is used to specify which bits
must be the same as the preset Identif ier and which bits need not be judged. 32-bit mask
mode example is shown in
Figure 22-7. 32-bit mask mode filter
.
Figure 22-7. 32-bit mask mode filter
FDATA1[31:21]
FDATA1[20:3]
FDATA1[2:0]
SFID[10:0]
EFID[17:0]
FF
FT
0
FDATA0[31:21]
FDATA0[20:3]
FDATA0[2:0]
ID
Mask
Figure 22-8. 16-bit mask mode filter
FDATA0[15:5]
FDATA0[4:0]
SFID[10:0]
FT
FF EFID[17:15]
FDATA1[15:5]
FDATA1[4:0]
SFID[10:0]
FT
FF EFID[17:15]
FDATA0[31:21]
FDATA0[20:16]
FDATA1[31:21]
FDATA1[20:16]
ID
Mask
List mode
The f ilter consists of f rame identifiers. The f ilter can determine whether a f rame will be
discarded or not. When one frame arrived, the filter will check which member can match the
identifier of the frame.
32-bit list mode example is shown in
Figure 22-9. 32-bit list mode filter
.
Figure 22-9. 32-bit list mode filter
FDATA1[31:21]
FDATA1[20:3]
FDATA1[2:0]
SFID[10:0]
EFID[17:0]
FF
FT
0
FDATA0[31:21]
FDATA0[20:3]
FDATA0[2:0]
ID
ID
Figure 22-10. 16-bit list mode filter
FDATA0[15:5]
FDATA0[4:0]
SFID[10:0]
FT
FF EFID[17:15]
FDATA1[15:5]
FDATA1[4:0]
SFID[10:0]
FT
FF EFID[17:15]
FDATA0[31:21]
FDATA0[20:16]
FDATA1[31:21]
FDATA1[20:16]
ID
Mask