Renesas H8S Family Hardware Manual page 832

Section 20 Ethernet Controller (EtherC)
(1) Write to PHY interface register
MMD = 0
MDC = 1
(2) Read from PHY
interface register read
MMD = 0
MMC = 1
MDI is read data
(3) Write to PHY interface register
MMD = 0
MDC = 0
(1) Write to PHY interfaceregister
Figure 20.11 Independent Bus Release Flowchart (IDLE in Write in Figure 20.7)
Rev. 1.00 Mar. 12, 2008 Page 784 of 1178
REJ09B0403-0100
Figure 20.10 1-Bit Data Read Flowchart
MMD = 0
MDC = 0
MDC
MDI
(1) (2) (3)
MDC
MDO
(1)