AM79C976 Advanced Micro Devices, AM79C976 Datasheet - Page 78

• Manufacturer Part Number: AM79C976
• Description: PCnet-PRO 10/100 Mbps PCI Ethernet Controller
• Manufacturer: Advanced Micro Devices

VLAN Support
Virtual Bridged Local Area Network (VLAN) tags are
defined in IEEE Std 802.3ac-1998. A VLAN tag is a
4-byte quantity that is inserted between the Source
Address field and the Length/Type field of a basic 802.3
MAC frame. The VLAN tag consists of a Length/Type
field that contains the value 8100h and a 16-bit Tag
Control Information (TCI) field. The TCI field is further
78
Offset
(hex)
AC
9C
A0
A4
A8
B0
B4
B8
98
XmtPkts1024to1518Octets RMON etherStatsPkts1024to1518Octets
Transmit Counter Name
XmtPkts512to1023Octets RMON etherStatsPkts512to1023Octets
XmtPkts128to255Octets
XmtPkts256to511Octets
XmtPkts65to127Octets
XmtBackPressure
XmtPkts64Octets
XmtOversizePkts
XmtFlowCtrl
PAUSEMACCtrlFramesTransmitted
RMON etherStatsPkts64Octets
RMON etherStatsPkts65to127Octets
RMON etherStatsPkts128to255Octets
RMON etherStatsPkts256to511Octets
MIB Object Supported
P R E L I M I N A R Y
Am79C976
divided into a 3-bit User Priority field, a 1-bit Canonical
Format Indicator (CFI), and a 12-bit VLAN Identifier.
A frame that has no VLAN tag is said to be untagged.
A frame with a VLAN tag whose VLAN Identifier field
contains the value 0 is said to be priority-tagged. A
frame with a VLAN tag with a non-zero VLAN Identifier
field is said to be VLAN-tagged.
The format of a VLAN-tagged frame is shown in
Figure 32.
The total number of back pressure collisions
generated.
The total number of PAUSE packets
generated and transmitted by the controller
hardware.
The total number of packets (excluding error
packets) that are 64 bytes long.
The total number of packets transmitted
(excluding error packets) that are 65 bytes to
127 bytes long, inclusive.
The total number of packets transmitted
(excluding error packets) that are 128 bytes to
255 bytes long, inclusive.
The total number of packets transmitted
(excluding error packets) that are 256 bytes to
511 bytes long, inclusive.
The total number of packets transmitted
(excluding error packets) that are 512 bytes to
1023 bytes long, inclusive
The total number of packets transmitted
(excluding error packets) that are 1024 bytes
to 1518 (1522 when VLAN set) bytes long,
inclusive.
The total number of packets transmitted
(excluding error packets) that are longer than
1518 (1522 when VLAN set) bytes.
Description of Counter/Comments
8/01/00