Intel 82555 manual Transmit Packet Timing Parameters, Squelch Test Timing Parameters

82555 — Networking Silicon

11.4.4Transmit Packet Timing Parameters

	Symbol	Parameter	Conditions	Min	Typ	Max	Units
T15	TXEN_ST	TXC on first TXEN active to start	100 Mbps	10		12	bits
		of frame
T15a	TXEN_ST	TXC on first TXEN active to start	10 Mbps	3.5		5	bits
		of frame
T16	TXEN_CRSH	TXC on first TXEN active to	100 Mbps			4	bits
		rising edge of CRS
T16a	TXEN_CRSH	TXC on first TXEN active to	10 Mbps			1.5	bits
		rising edge of CRS
T17	TXEN_END	TXC on first TXEN inactive to	100 Mbps			17	bits
		end of frame
T17a	TXEN_END	TXC on first TXEN inactive to	10 Mbps			5	bits
		end of frame
T18	TXEN_CRSL	TXC on first TXEN inactive to	100 Mbps			11	bits
		falling edge of CRS
T18a	TXEN_CRSL	TXC on first TXEN inactive to	10 Mbps			6	bits
		falling edge of CRS
T19	TEOF	End of frame high time	10 Mbps	250		350	ns

TXCLK
TXEN	T16,T16a
		T18,T18a
CRS
	T15,T15a	T17,T17a
Frame On link		Valid Frame Data

Figure 19. Transmit Frame Timing Parameters

11.4.5Squelch Test Timing Parameters

	Symbol	Parameter	Conditions	Min	Typ	Max	Units
T20	TSQE_DEL	Collision detect heartbeat delay	10 Mbps	7		8	bits
T21	TSQE_DUR	Collision detect heartbeat	10 Mbps	9		11	bits
		duration

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