82801FB Datasheet, PDF (110/786 Pages) Intel Corporation – Intel I/O Controller Hub 6 (ICH6) Family

Functional Description
Figure 5-2. 64-Word EEPROM Read Instruction Waveform
EE_SHCLKK
EE_CS
EE_DIN
EE_DOUT
A₅
A₄
A₃
A₂
AA₁₀ A₀
READ OP code
D₁₅
D₀
5.3.3
5.3.3.1
The LAN controller performs an automatic read of seven words (0h, 1h, 2h, Ah, Bh, Ch, and Dh)
of the EEPROM after the de-assertion of Reset.
CSMA/CD Unit
The ICH6 integrated LAN controller CSMA/CD unit implements both the IEEE 802.3 Ethernet
10 Mbps and IEEE 802.3u Fast Ethernet 100 Mbps standards. It performs all the CSMA/CD
protocol functions (e.g., transmission, reception, collision handling, etc.). The LAN controller
CSMA/CD unit interfaces to the 82562ET/EM/EZ/EX 10/100 Mbps Ethernet through the ICH6’s
LAN Connect interface signals.
Full Duplex
When operating in full-duplex mode, the LAN controller can transmit and receive frames
simultaneously. Transmission starts regardless of the state of the internal receive path. Reception
starts when the platform LAN Connect component detects a valid frame on its receive differential
pair. The ICH6 integrated LAN controller also supports the IEEE 802.3x flow control standard,
when in full-duplex mode.
The LAN controller operates in either half-duplex mode or full-duplex mode. For proper operation,
both the LAN controller CSMA/CD module and the discrete platform LAN Connect component
must be set to the same duplex mode. The CSMA duplex mode is set by the LAN Controller
Configure command or forced by automatically tracking the mode in the platform LAN Connect
component. Following reset, the CSMA defaults to automatically track the platform LAN Connect
component duplex mode.
The selection of duplex operation (full or half) and flow control is done in two levels: MAC and
LAN Connect.
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Intel^® I/O Controller Hub 6 (ICH6) Family Datasheet