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MPC8641 and MPC8641D Integrated Host Processor Hardware Specifications, Rev. 0
42
Freescale Semiconductor
Ethernet Management Interface Electrical Characteristics
Figure 21 provides the AC test load for eTSEC.
Figure 21. eTSEC AC Test Load
Figure 22 shows the RMII receive AC timing diagram.
Figure 22. RMII Receive AC Timing Diagram
9
Ethernet Management Interface Electrical
Characteristics
The electrical characteristics specified here apply to MII management interface signals MDIO
(management data input/output) and MDC (management data clock). The electrical characteristics for
RXD[1:0], CRS_DV, RX_ER hold time to REF_CLK
rising edge
tRMRDX
2.0
—
ns
Note:
1. The symbols used for timing specifications herein follow the pattern of t(first two letters of functional block)(signal)(state)
(reference)(state) for inputs and t(first two letters of functional block)(reference)(state)(signal)(state) for outputs. For example,
tMRDVKH symbolizes MII receive timing (MR) with respect to the time data input signals (D) reach the valid state (V)
relative to the tMRX clock reference (K) going to the high (H) state or setup time. Also, tMRDXKL symbolizes MII
receive timing (GR) with respect to the time data input signals (D) went invalid (X) relative to the tMRX clock reference
(K) going to the low (L) state or hold time. Note that, in general, the clock reference symbol representation is based
on three letters representing the clock of a particular functional. For example, the subscript of tMRX represents the
MII (M) receive (RX) clock. For rise and fall times, the latter convention is used with the appropriate letter: R (rise)
or F (fall).
Table 37. RMII Receive AC Timing Specifications (continued)
At recommended operating conditions with L/TVDD of 3.3 V ± 5%.
Parameter/Condition
Symbol 1
Min
Typ
Max
Unit
Output
Z0 = 50 Ω
LVDD/2
RL = 50 Ω
REF_CLK
RXD[1:0]
tRMRDX
tRMR
tRMRH
tRMRR
tRMRF
CRS_DV
RX_ER
tRMRDV
Valid Data