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4 transmit packet timing parameters, Figure 19. transmit frame timing parameters, 5 squelch test timing parameters – Intel 82555 User Manual

Page 52: Transmit packet timing parameters, Squelch test timing parameters

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82555 — Networking Silicon

48

Datasheet

11.4.4

Transmit Packet Timing Parameters

11.4.5

Squelch Test Timing Parameters

Symbol

Parameter

Conditions

Min

Typ

Max

Units

T15

T

XEN_ST

TXC on first TXEN active to start
of frame

100 Mbps

10

12

bits

T15a

T

XEN_ST

TXC on first TXEN active to start
of frame

10 Mbps

3.5

5

bits

T16

T

XEN_CRSH

TXC on first TXEN active to
rising edge of CRS

100 Mbps

4

bits

T16a

T

XEN_CRSH

TXC on first TXEN active to
rising edge of CRS

10 Mbps

1.5

bits

T17

T

XEN_END

TXC on first TXEN inactive to
end of frame

100 Mbps

17

bits

T17a

T

XEN_END

TXC on first TXEN inactive to
end of frame

10 Mbps

5

bits

T18

T

XEN_CRSL

TXC on first TXEN inactive to
falling edge of CRS

100 Mbps

11

bits

T18a

T

XEN_CRSL

TXC on first TXEN inactive to
falling edge of CRS

10 Mbps

6

bits

T19

T

EOF

End of frame high time

10 Mbps

250

350

ns

Figure 19. Transmit Frame Timing Parameters

TXEN

CRS

Valid Frame Data

TXCLK

Frame On link

T15,T15a

T16,T16a

T17,T17a

T18,T18a

Symbol

Parameter

Conditions

Min

Typ

Max

Units

T20

T

SQE_DEL

Collision detect heartbeat delay

10 Mbps

7

8

bits

T21

T

SQE_DUR

Collision detect heartbeat
duration

10 Mbps

9

11

bits