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ADM5120
Register Description
Bits
Type Name
Description
Initial value
ADMtek Inc.
4-9
00: disable, BC will be blocked, if
01=64 blocks
10=48 blocks
11=32 blocks
11:10 RW
Max_len
Maximum packet length:
00: 1536,
01: 1518,
10: 1522,
11: reserved
00
12
RW
Dis_colabt
1: Disable collision 16 packet abort
14:13 RW
Hash_alg
MAC address hashing algorithm:
00: direct mode, using last 10-bit as hashing address
01: XOR48 mode
10: XOR32 mode,
11:reserved
00
15
RW
force_bk
Disable the collision back off timer:
1: re-transmit immediately after collision,
0: follow standard
0
19:16 RW
BP_num
Back pressure jam number: the consecutive jam time
when back pressure,
Default = 1010, 10 packet jam then one no-jam
1010
21:20 RW
BP_mode
Back pressure mode :
00: disable
01: BP jam, the jam number is set by BP_num
10: BP jamALL, jam packet until the BP condition is
released (default),
11: BP carrier, use carrier insertion to do back pressure
10
22
RW
Rsrv_MC
Reserved MC filtering:
1: filtered,
0: forwarded
Note: Reserved MC = 01-80-c2-00-00-00 (BPDU) and
01-80-c2-00-00-02 to 01-80-c2-00-00-0f
0
23
RO
BISR_disable
Build-in self repair disable
→
0: enable skip function
(default, from pin A[5])
0
24 RW disMII_wasTX
MII0 port disable was_transmit:
1: disable was_transmit (good for late CRS PHY, like
HPNA2.0 or power-LAN),
0: enable
0
25 RW BISS_disable
Build-in self skip disable: 0 = enable skip function
(default, from pin A[6])
0
27:26 RW BISS_TH
The threshold of BISS:
00:skip if fail 16 (default, from pins)
01:skip if fail 48
10:skip if fail 64
11:skip if fail 8 blocks
00