dm9332 Davicom Semiconductor, Inc., dm9332 Datasheet - Page 47

• Manufacturer Part Number: dm9332
• Description: 10/100mbps Ethernet Fiber/twisted Pair Single Chip Media Converter
• Manufacturer: Davicom Semiconductor, Inc.

untagged packet enters the port, and recalculate
CRC before delivering it.
port.
without modification.
mechanism for multimedia communication such as
VoIP and video conferencing.
Port-based, 802.1p-based and DiffServ-based priority.
See next section for more detail. The DM9332 offers
four level queues for transmit on per-port based.
algorithms: Weighted Fair Queuing and Strict Priority
Queuing. Weighted Fair Queuing (WFQ) based on
their priority and queue weight. Queues with larger
weights get more service than smaller. This
mechanism can get highly efficient bandwidth and
smooth the traffic. Strict Priority Queuing (SPQ)
based on priority only. The Packet on the highest
priority
highest-priority queue is work until last queue empties,
and so on. This feature can be set in bit 5 of register
6Dh.
Preliminary datasheet
DM9332-15-DS-P01
August 26, 2009
(4). Receive tagged packet and forward to Tag
Received packet will forward to destination port
The DM9332 supports Quality of Service (QoS)
The DM9332 provides three priority classifications:
The DM9332 provides two packet scheduling
9.2.14 Priority Support
The DM9332 will insert the PVID tag when an
queue
is
transmitted
10/100Mbps Ethernet Fiber/Twisted Pair Single Chip Media Converter
first.
The
next
default. Each port has a 2-bit priority value as index
for splitting ingress packets to the corresponding
transmit queue. This value can be set in bit 0 and 1 of
register 6Dh.
6Dh, it is enabled by default.
received packet with 802.1p VLAN tag, and maps this
field against VLAN Priority Map Registers (D0h~D1h)
to determine which transmit queue is designated. The
VLAN Priority Map is programmable.
6-bit of the ToS field in standard IPv4 header, and
maps this field against ToS Priority Map Registers
(C0h~CFh) to determine which transmit queue is
designated. The ToS Priority Map is programmable
too. In addition, User can only refer to most
significant 3-bit of the ToS field optionally, see bit 7 of
register 53h.
Port based priority is the simplest scheme and as
802.1p priority can be disabled by bit 2 of register
The DM9332 extracts 3-bit priority field from
DiffServ based priority uses the most significant
9.2.14.1 Port-Based Priority
9.2.14.2 802.1p-Based Priority
9.2.14.3 DiffServ-Based Priority
DM9332
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