
NUC970 Technical Reference Manual
Publication Release Date: Dec. 15, 2015
- 612 -
Revision V1.30
NUC97
0
T
E
CHNIC
A
L
RE
F
E
RE
N
CE
MA
NUA
L
EMAC n CAM 15 Most Significant Word Register (EMACn_CAM15M)
The EMAC is equipped with 16 CAM entries. In these 16 CAM entries, 13 entries (entry 0~12) are
to keep destination MAC address for packet recognition, and the other 3 entries (entry 13~15) are
for PAUSE control frame transmission. Each CAM entry consists of 6 bytes. Consequently, 2
register are used for each CAM entry.
For packet recognition, a register pair {EMACn_CAMxM, EMACn_CAMxL} represents a CAM
entry and can keep a destination MAC address. The corresponding CAM enable bit CAMxEN
(EMACn_CAMEN[x]) is also needed be enabled. The x can be the 0 to 12.
The register pairs {EMACn_CAM13M, EMACn_CAM13L}, {EMACn_CAM14M, EMACn_CAM14L}
and {EMACn_CAM15M, EMACn_CAM15L} are used for flow control function.
Register
Offset
R/W Description
Reset Value
EMACn_CAM15M
n=0,1
E0x080 R/W EMAC n CAM 15 Most Significant Word Register
0x0000_0000
31
30
29
28
27
26
25
24
Length_Type
23
22
21
20
19
18
17
16
Length_Type
15
14
13
12
11
10
9
8
OP_Code
7
6
5
4
3
2
1
0
OP_Code
Bits
Description
[31:16]
Length_Type
Length/Type Field of PAUSE Control Frame
In the PAUSE control frame, a length/type field defined and is 16‟h8808.
[15:0]
OP_Code
OP Code Field of PAUSE Control Frame
In the PAUSE control frame, an op code field defined and is 16‟h0001.