KS8997 Micrel Inc, KS8997 Datasheet - Page 20

• 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

KS8997
VLAN Operation
The VLAN’s are setup by programming the VLAN Mask Registers in the “EEPROM Memory Map” section. The perspective
of the VLAN is from the input port and which output ports it sees directly through the switch. For example if port 1 only
participated in a VLAN with ports 2 and 8 then one would set bits 0 and 6 in register 13 (Port 1 VLAN Mask Register). Note
that different ports can be setup independently. An example of this would be where a router is connected to port 8 and each
of the other ports would work autonomously. In this configuration ports 1 through 7 would only set the mask for port 8 and port
8 would set the mask for ports 1 through 7. In this way the router could see all ports and each of the other individual ports would
only communicate with the router.
All multicast and broadcast frames adhere to the VLAN configuration. Unicast frame treatment is a function of register 2 bit
0. If this bit is set then unicast frames only see ports within their VLAN. If this bit is cleared unicast frames can traverse VLAN’s.
VLAN tags can be added or removed on a per port basis. Further, there are provisions to specify the tag value to be inserted
on a per port basis.
The table below briefly summarizes VLAN features. For more detailed settings see “EEPROM Memory Map” section.
Station MAC Address (control frames only)
The MAC source address can be programmed as used in flow control frames. The table below briefly summarizes this
progammable feature.
KS8997
Register(s)
4-11
4-11
2
13-20
22-38
Register(s)
48-53
Bit(s)
2
1
0
7-0
7-0
Bit(s)
7-0
Global/Port
Port
Port
Global
Port
Port
Global/Port
Global
Description
Insert VLAN Tags: If specified, will add VLAN tags to frames without existing tags
Strip VLAN Tags: If specified, will remove VLAN tags from frames if they exist
VLAN Enforcement: Allows unicast frames to adhere or ignore the VLAN configuration
VLAN Mask Registers: Allows configuration of individual VLAN grouping.
VLAN Tag Insertion Values: Specifies the VLAN tag to be inserted if enabled (see above)
Description
Station MAC Address: Used as source address for MAC control frames as used in full-
duplex flow control mechanisms.
Table 2. VLAN Control
Table 3. Misc. Control
20
August 2003
Micrel