Small Footprint RMII 10/100 Ethernet Transceiver with HP Auto-MDIX Support
Datasheet
Read Cycle
MDC
MDI0
...
...
D1
D15 D14
D0
32 1's
0
1
1
0
A4 A3 A2 A1 A0 R4 R3 R2 R1 R0
Start of
Frame
OP
Code
Turn
Around
Preamble
PHY Address
Register Address
Data
Data To Phy
Data From Phy
Figure 4.10 MDIO Timing and Frame Structure - READ Cycle
Write Cycle
MDC
...
D15 D14
D1
D0
32 1's
0
1
0
1
A4 A3 A2 A1 A0 R4 R3 R2 R1 R0
PHY Address Register Address
...
MDIO
Start of
Frame
OP
Code
Turn
Around
Preamble
Data
Data To Phy
Figure 4.11 MDIO Timing and Frame Structure - WRITE Cycle
SMSC LAN8720/LAN8720i
Revision 1.0 (05-28-09)
DATA3S5HEET