Destination Address To 6-Bit Hash - Motorola ColdFire MCF5281 User Manual

Functional Description
The effectiveness of the hash table declines as the number of addresses increases.
The hash table registers must be initialized by the user. The CRC32 polynomial to use in
computing the hash is:
32
X +
A table of example Destination Addresses and corresponding hash values is included below
for reference.
17-14
26 23 22 16 12
X + X + X + X + X
Table 17-7. Destination Address to 6-Bit Hash
48-bit DA
65:ff:ff:ff:ff:ff
55:ff:ff:ff:ff:ff
15:ff:ff:ff:ff:ff
35:ff:ff:ff:ff:ff
b5:ff:ff:ff:ff:ff
95:ff:ff:ff:ff:ff
d5:ff:ff:ff:ff:ff
f5:ff:ff:ff:ff:ff
db:ff:ff:ff:ff:ff
fb:ff:ff:ff:ff:ff
bb:ff:ff:ff:ff:ff
8b:ff:ff:ff:ff:ff
0b:ff:ff:ff:ff:ff
3b:ff:ff:ff:ff:ff
7b:ff:ff:ff:ff:ff
5b:ff:ff:ff:ff:ff
27:ff:ff:ff:ff:ff
07:ff:ff:ff:ff:ff
57:ff:ff:ff:ff:ff
77:ff:ff:ff:ff:ff
f7:ff:ff:ff:ff:ff
c7:ff:ff:ff:ff:ff
97:ff:ff:ff:ff:ff
a7:ff:ff:ff:ff:ff
MCF5282 User's Manual
11 10 8 7 5
+ X + X + X + X + X +
6-bit Hash (in Hash Decimal
hex) Value
0x0
0x1
0x2
0x3
0x4
0x5
0x6
0x7
0x8
0x9
0xa 10
0xb 11
0xc 12
0xd 13
0xe 14
0xf 15
0x10 16
0x11 17
0x12 18
0x13 19
0x14 20
0x15 21
0x16 22
0x17 23
4 2
X + X + X + 1
0
1
2
3
4
5
6
7
8
9
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