AM79C901AJCT AMD [Advanced Micro Devices], AM79C901AJCT Datasheet - Page 25

• Manufacturer Part Number: AM79C901AJCT
• Description: HomePHY Single-Chip 1/10 Mbps Home Networking PHY
• Manufacturer: AMD [Advanced Micro Devices]

Note: CLS will be asserted some time after the preamble and SFD have been clocked in. TXCLK and RXCLK
are then clocked until RXCRS drops. TXEN drops about 32 clocks after CLS was asserted. RXCRS and CLS
are dropped together after more than 500 clocks (about 120 s). TXCLK and RXCLK keep toggling for approx-
imately another 100 clock cycles, when the system returns to the Idle state.
RXCRS
RXCLK
RXDAT
TXDAT
Note: Once TXEN is cleared, the last symbol gets encoded and transmitted, the looped-back data is presented
back to the MAC, and RXCRS falls. Once RXCRS falls, TXCLK and RXCLK toggle for 96 clocks, after which
the system returns to the Idle state.
TXCLK
TXEN
CLS
RXCRS
RXDAT
TXDAT
RXCLK
TXCLK
TXEN
CLS
Figure 6. TXPKT - TXEN Cleared
Figure 7. TXPKT - CLS Asserted
P R E L I M I N A R Y
Am79C901A
22304B-8
22304B-9
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