Freescale Semiconductor, Inc.

RX_CLK (input)

RXD[3:0] (inputs)

RX_DV

RX_ER

M1

M3

M4

M2

Freescale Semiconductor, Inc.

Figure 7-1. MII Receive Signal Timing Diagram

The receiver functions correctly up to a RX_CLK maximum frequency of 25 MHz +1%. There is no minimum frequency requirement. In addition, the processor clock frequency must exceed the RX_CLK frequency - 1%.

Table 7-1. MII Receive Signal Timing

Num

Characteristic

Min

Max

Unit

 

 

 

 

 

M1

RXD[3:0], RX_DV, RX_ERR to RX_CLK setup

5

Ñ

ns

 

 

 

 

 

M2

RX_CLK to RXD[3:0], RX_DV, RX_ERR hold

5

Ñ

ns

 

 

 

 

 

M3

RX_CLK pulse width high

35%

65%

RX_CLK period

 

 

 

 

 

M4

RX_CLK pulse width low

35%

65%

RX_CLK period

 

 

 

 

 

7.3.2 MII Transmit Signal Timing (TXD[3:0], TX_EN, TX_ER, TX_CLK)

Table 7-2 provides information on the MII transmit signal timing, shown in Figure 7-2.

The transmitter functions correctly up to a TX_CLK maximum frequency of 25 MHz +1%. There is no minimum frequency requirement. In addition, the processor clock frequency must exceed the TX_CLK frequency - 1%.

Table 7-2. MII Transmit Signal Timing

Num

Characteristic

Min

Max

Unit

 

 

 

 

 

M5

TX_CLK to TXD[3:0], TX_EN, TX_ER invalid

5

Ñ

ns

 

 

 

 

 

M6

TX_CLK to TXD[3:0], TX_EN, TX_ER valid

Ñ

25

 

 

 

 

 

 

M7

TX_CLK pulse width high

35%

65%

TX_CLK period

 

 

 

 

 

M8

TX_CLK pulse width low

35%

65%

TX_CLK period

 

 

 

 

 

Figure 7-2 shows the MII transmit signal timing diagram.

7-2MPC860T (Rev. D) Fast Ethernet Controller Supplement MOTOROLA

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Freescale Semiconductor MPC860T MII Transmit Signal Timing TXD30, TXEN, TXER, Txclk, MII Receive Signal Timing, Rxdv Rxer