8101 Datasheet, PDF (44/172 Pages) LSI Computer Systems – Gigabit Ethernet Controller

• Adds the end of packet delimiter
• Adds the idle code stream
• Formats the packet according to the 10B PHY format defined in IEEE
802.3z and shown in Figure 2.3
The 8B10B encoded data stream is then sent to the transmit 10-bit PHY
interface for transmission.
The transmit 8B10B PCS section also generates the AutoNegotiation
code stream when the controller is in the AutoNegotiation process.
The receive 8B10B PCS section takes the 8B10B encoded packet data
from the incoming 10-bit PHY interface and:
• Acquires and maintains word synchronization
• Strips off the start of packet delimiter
• Strips off the end of packet delimiter
• Strips off the idle code stream
• Decodes the data with the 8B10B decoder
• Converts the packet to the Ethernet packet format shown in
Figure 2.2
The Ethernet packet is then sent to the receive MAC for processing.
The receive 8B10B PCS section also decodes the AutoNegotiation code
stream when the controller is in the AutoNegotiation process.
2.11.1 8B10B Encoder
The 8B10B encoder converts each data byte of a packet into a unique
10-bit word as defined in IEEE 802.3z and shown in Table 2.7 (in
abbreviated form).
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Functional Description
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