am79c901a Advanced Micro Devices, am79c901a Datasheet - Page 23

• Manufacturer Part Number: am79c901a
• Description: Homephy Single-chip 1/10 Mbps Home Networking Phy
• Manufacturer: Advanced Micro Devices

Note: RXCLK becomes disabled as soon as RXCRS is asserted.
Note: RXCLK and TXCLK are unrelated to each other during this time. When a symbol has been received and
decoded, RXCLK toggles in order to shift out the three to six bits encoded in the symbol. The middle portion of
this diagram shows the end of the preamble, followed by an SFD and the beginning of the data. RXCRS will fall
after the last received symbol. Once RXCRS falls, RXCLK and TXCLK are toggled continuously for 96 cycles,
after which the PHY returns to the Idle state.
RXCRS
RXDAT
TXDAT
RXCLK
TXCLK
TXEN
CLS
RXCRS
RXDAT
RXCLK
TXCLK
TXDAT
TXEN
CLS
Figure 2. RXPKT - RXCRS Asserted
Figure 3. RXPKT - RXCRS Cleared
P R E L I M I N A R Y
Am79C901A
22304B-4
22304B-5
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