Datasheet

Micrel, Inc. KS8999
January 2005
29
KS8999
EEPROM Memory
Address Name Description Default
(chip) Value
0 7-0 Signature byte 1. Value = “55” 0x55
1 7-0 Signature byte 2. Value = “99” 0x99
General Control Register
2 7-4 Reserved –set to zero 0000
2 3-2 Priority control scheme (all ports)
00 = Transmit all high priority before any low priority
01= Transmit high and low priority at a 10:1 ratio
10 = Transmit high and low priority at a 5:1 ratio
11 = Transmit high and low priority at a 2:1 ratio
00
2 1 Priority buffer reserve for high priority traffic
1 = Reserve 6KB of buffer space for high priority
0 = None reserved
0
2 0 VLAN enforcement
1 = All unicast frames adhere to VLAN configuration
0 = Unicast frames ignore VLAN configuration
0
Priority Classification Control –802.1p tag field
3 7 1 = State “111”is high priority
0 = State “111”is low priority
1
3 6 1 = State “110”is high priority
0 = State “110”is low priority
1
3 5 1 = State “101”is high priority
0 = State “101”is low priority
1
3 4 1 = State “100”is high priority
0 = State “100”is low priority
1
3 3 1 = State “011”is high priority
0 = State “011”is low priority
0
3 2 1 = State “010”is high priority
0 = State “010”is low priority
0
3 1 1 = State “001”is high priority
0 = State “001”is low priority
0
3 0 1 = State “000”is high priority
0 = State “000”is low priority
0
Port 1 Control Register
4 7-6 Reserved –set to zero 00
4 5 TOS priority classification enable for port 1
1 = Enable
0 = Disable
0
4 4 802.1p priority classification enable for port 1
1 = Enable
0 = Disable
0
4 3 Port based priority classification for port 1
1 = High priority
0 = Low priority
0
4 2 Insert VLAN tags for port 1 if non-existent
1 = Enable
0 = Disable
0
4 1 Strip VLAN tags for port 1 if existent
1 = Enable
0 = Disable
0
4 0 Enable high and low output priority queues for port 1
1 = Enable
0 = Disable
0