KS8997 Micrel Inc, KS8997 Datasheet - Page 21

• Manufacturer Part Number: KS8997
• Description: IC SWITCH 10/100 8PORT 128PQFP
• Manufacturer: Micrel Inc

Specifications of KS8997

• Applications: *
• Mounting Type: Surface Mount
• Package / Case: 128-MQFP, 128-PQFP
• Fiber Support: No
• Integrated Led Drivers: Yes
• Phy/transceiver Interface: MII
• Power Supply Type: Analog/Digital
• Package Type: PQFP
• Data Rate (typ): 10/100Mbps
• Vlan Support: Yes
• Operating Temperature (max): 70C
• Operating Temperature (min): 0C
• Pin Count: 128
• Mounting: Surface Mount
• Jtag Support: No
• Operating Temperature Classification: Commercial
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

EEPROM Operation
The EEPROM interface utilizes 2 pins that provide a clock and a serial data path. As part of the initialization sequence, the
KS8997 reads the contents of the EEPROM and loads the values into the appropriate registers. Note that the first two bytes
in the EEPROM must be “55” and “99” respectively for the loading to occur properly. If these first two values are not correct,
all other data will be ignored.
Data start and stop conditions are signaled on the data line as a state transition during clock high time. A high to low transition
indicates start of data and a low to high transition indicates a stop condition. The actual data that traverses the serial line
changes during the clock low time.
The KS8997 EEPROM interface is compatible with the Atmel AT24C01A part. Further timing and data sequences can be found
in the Atmel AT24C01A specification.
EEPROM Memory Map
August 2003
KS8997
Address
0
1
General Control Register
2
2
2
2
Priority Classification Control - 802.1p tag field
3
3
3
3
3
3
3
3
Port 1 Control Register
4
4
4
Name
7-0
7-0
7-4
3-2
1
0
7
6
5
4
3
2
1
0
7-6
5
4
Description
Signature byte 1. Value = “55”
Signature byte 2. Value = “99”
Reserved - set to zero
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
Priority buffer reserve for high priority traffic
1 = Reserve 6KB of buffer space for high priority
0 = None reserved
VLAN enforcement
1 = All unicast frames adhere to VLAN configuration
0 = Unicast frames ignore VLAN configuration
1 = State “111” is high priority
0 = State “111” is low priority
1 = State “110” is high priority
0 = State “110” is low priority
1 = State “101” is high priority
0 = State “101” is low priority
1 = State “100” is high priority
0 = State “100” is low priority
1 = State “011” is high priority
0 = State “011” is low priority
1 = State “010” is high priority
0 = State “010” is low priority
1 = State “001” is high priority
0 = State “001” is low priority
1 = State “000” is high priority
0 = State “000” is low priority
Reserved - set to zero
TOS priority classification enable for port 1
1 = Enable
0 = Disable
802.1p priority classification enable for port 1
1 = Enable
0 = Disable
21
Default
(chip) Value
0x55
0x99
0000
00
0
0
1
1
1
1
0
0
0
0
00
0
0
KS8997
Micrel