KSZ8995M Micrel Inc, KSZ8995M Datasheet - Page 55

• Manufacturer Part Number: KSZ8995M
• Description: IC SWITCH 10/100 5PORT 128PQFP
• Manufacturer: Micrel Inc

Specifications of KSZ8995M

• Applications: *
• Mounting Type: Surface Mount
• Package / Case: 128-MQFP, 128-PQFP
• Number Of Primary Switch Ports: 5
• Internal Memory Buffer Size: 64
• Operating Supply Voltage (typ): 1.8/2.5/3.3V
• Fiber Support: Yes
• Integrated Led Drivers: Yes
• Phy/transceiver Interface: MII/SNI
• 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 Supply Voltage (max): 1.9/2.6/3.6V
• Operating Supply Voltage (min): 1.7/2.4/3V
• Operating Temperature Classification: Commercial
• Data Rate: 100Mbps
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 576-1607 - BOARD EVAL EXPERIMENT KSZ8995MA
• Lead Free Status / RoHS Status: Compliant, Lead free / RoHS Compliant
• Other names: 576-1038

VLAN Address
VLAN table is used to do VLAN table look-up. If 802.1q VLAN mode is enabled (Register 5 bit 7 =1), this table will be used
to retrieve VLAN information that the ingress packet is associated with. The information includes FID (fiter ID), VID(VLAN ID),
VLAN membership described below:
If 802.1q VLAN mode is enabled, KS8995M will assign a VID to every ingress packet. If the packet is untagged or tagged with
a null VID, the packet is assigned with the default port VID of the ingress port. If the packet is tagged with non null VID, the
VID in the tag will be used. The look-up process will start from the VLAN table look-up. If the VID is not valid, the packet will
be dropped and no address learning will take place. If the VID is valid, the FID is retrieved. The FID+DA and FID+SA lookups
are performed. The FID+DA look-up determines the forwarding ports. If FID+DA fails, the packet will be broadcasted to all the
members (excluding the ingress port) of the VLAN. If FID+SA fails, the FID+SA will be learned.
Examples:
(1) VLAN Table Read (read the 3rd entry)
(2) VLAN Table Write (write the 7th entry)
December 2003
KS8995M
Address
Format of Static VLAN Table (16 entries)
21
20-16
15-12
11-0
Write to reg110 with 0x14 (read VLAN table selected)
Write to reg111 with 0x2 (trigger the read operation)
Then
Read reg118 (VLAN table bits 21-16)
Read reg119 (VLAN table bits 15-8)
Read reg120 (VLAN table bits 7-0)
Write to reg118 (VLAN table bits 21-16)
Write to reg119 (VLAN table bits 15-8)
Write to reg120 (VLAN table bits 7-0)
Write to reg110 with 0x04 (write static table selected)
Write to reg111 with 0x6 (trigger the write operation)
Name
Valid
Membership
FID
VID
Description
1, the entry is valid
0, entry is invalid
Specify which ports are members of the VLAN.
If a DA look-up fails (no match in both static and
dynamic tables), the packet associated with this VLAN
will be forwarded to ports specified in this field.
Eg. 11001 means port 5,4, and 1 are in this VLAN.
Filter ID. KS8995M supports 16 active VLANs
represented by these four bit fields. FID is the mapped
ID. If 802.1q VLAN is enabled, the look-up will be based
on FID+DA and FID+SA.
EEE 802.1q 12 bit VLAN ID
Table 13. VLAN Table
55
Mode
R/W
R/W
R/W
R/W
Default
1
11111
0
1
M9999-120403
Micrel