DP83820BVUW National Semiconductor, DP83820BVUW Datasheet - Page 31

• Manufacturer Part Number: DP83820BVUW
• Description: IC INTERFACE CONTROLLER 208-PQFP
• Manufacturer: National Semiconductor

Specifications of DP83820BVUW

• Controller Type: Ethernet Controller, MAC/BIU
• Interface: IEEE 802.3
• Voltage - Supply: 3.3V
• Current - Supply: 150mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 208-MQFP, 208-PQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: *DP83820BVUW

3.0 Functional Description
3.13.5.2 Receive Data Flow with Priority Queueing
With Priority Queueing, it is still necessary to pre-allocate
buffers and descriptors. Each priority queue must have a
separate list of descriptors allocated. The receive data flow
is similar to the above with the following exceptions:
— The Receive state machine waits until packet data is
available, and the priority for the packet has been
determined from a VLAN tag (assumes priority 0 if no tag
is present). Using this information, the receive state
machine will then process descriptors as detailed above.
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— If no descriptors are available for the priority queue
— If no descriptors are available for the priority queue
matching the packet priority, the state machine will wait
for the system to append more descriptors to the
descriptor list and pulse the CR:RXEN and CR:RXPRI
controls.
matching the packet priority, the state machine will wait
for the system to append more descriptors to the
descriptor list and pulse the CR:RXEN and CR:RXPRI
controls.
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