MPC860DP datasheet(67/80 Pages) FREESCALE

67 / 80 page

MPC860 PowerQUICC™ Family Hardware Specifications, Rev. 8

Freescale Semiconductor

FEC Electrical Characteristics

13 FEC Electrical Characteristics

This section provides the AC electrical specifications for the Fast Ethernet controller (FEC). Note that the

timing specifications for the MII signals are independent of system clock frequency (part speed

designation). Also, MII signals use TTL signal levels compatible with devices operating at either 5.0 V or

3.3 V.

13.1

MII Receive Signal Timing (MII_RXD[3:0], MII_RX_DV, MII_RX_ER,

MII_RX_CLK)

The receiver functions correctly up to a MII_RX_CLK maximum frequency of 25 MHz + 1%. There is no

minimum frequency requirement. In addition, the processor clock frequency must exceed the

MII_RX_CLK frequency – 1%.

Table 29 provides information on the MII receive signal timing.

Figure 72 shows MII receive signal timing.

Figure 72. MII Receive Signal Timing Diagram

Table 29. MII Receive Signal Timing

Num

Characteristic

Min

Max

Unit

MII_RXD[3:0], MII_RX_DV, MII_RX_ER to MII_RX_CLK setup

—

MII_RX_CLK to MII_RXD[3:0], MII_RX_DV, MII_RX_ER hold

—

MII_RX_CLK pulse width high

35%

65%

MII_RX_CLK

period

MII_RX_CLK pulse width low

35%

65%

MII_RX_CLK

period

MII_RX_CLK (Input)

MII_RXD[3:0] (Inputs)

MII_RX_DV

MII_RX_ER

MPC860DP Datasheet(PDF) 67 Page - Freescale Semiconductor, Inc