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Tnetx4090 thunderswitch ii, Switch – Texas Instruments THUNDERSWITCH II TNETX4090 User Manual

Page 67

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TNETX4090

ThunderSWITCH II

9-PORT 100-/1000-MBIT/S ETHERNET

SWITCH

SPWS044E – DECEMBER 1997 – REVISED AUGUST 1999

67

POST OFFICE BOX 655303

DALLAS, TEXAS 75265

MII transmit (see Figure 22)

NO.

MIN

MAX

UNIT

1

td(Mxx_TXD)

Delay time, from Mxx_TCLK

to Mxx_TXD3–MxxTXD0 valid

5

15

ns

1

td(Mxx_TXEN)

Delay time, from Mxx_TCLK

to Mxx_TXEN valid

5

15

ns

1

td(Mxx_TXER)

Delay time, from Mxx_TCLK

to Mxx_TXER valid

5

15

ns

ОООООООООООООО

ОООООООООООООО

ОООООООООООООО

Mxx_TXD3–Mxx_TXD0

Mxx_TXEN
Mxx_TXER

1

Mxx_TCLK

Figure 22. MII Transmit

MII clock (see Figure 23)

NO.

MIN

MAX

UNIT

1

tr(Mxx_CLK)

Pulse width low Mxx_RCLK, Mxx_TCLK

35%

65%

2

th(Mxx_CLK)

Pulse width high Mxx_RCLK, Mxx_TCLK

35%

65%

3

tw(Mxx_CLK)

Cycle time Mxx_RCLK, Mxx_TCLK

2.5

25

MHz

Mxx_RCLK

Mxx_TCLK

1

2

3

Figure 23. MII Clock