Datasheet

DocID15818 Rev 11 119/178
STM32F20xxx Electrical characteristics
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Figure 48. Ethernet SMI timing diagram
Table 64 gives the list of Ethernet MAC signals for the RMII and Figure 49 shows the
corresponding timing diagram.
Figure 49. Ethernet RMII timing diagram
Table 63. Dynamics characteristics: Ethernet MAC signals for SMI
Symbol Rating Min Typ Max Unit
t
MDC
MDC cycle time (2.38 MHz) 411 420 425 ns
t
d(MDIO)
MDIO write data valid time 6 10 13 ns
t
su(MDIO)
Read data setup time 12 - - ns
t
h(MDIO)
Read data hold time 0 - - ns
Table 64. Dynamics characteristics: Ethernet MAC signals for RMII
Symbol Rating Min Typ Max Unit
t
su(RXD)
Receive data setup time 1 - -
ns
t
ih(RXD)
Receive data hold time 1.5 - -
t
su(CRS)
Carrier sense set-up time 0 - -
t
ih(CRS)
Carrier sense hold time 2 - -
t
d(TXEN)
Transmit enable valid delay time 9 11 13
t
d(TXD)
Transmit data valid delay time 9 11.5 14
ETH_MDC
ETH_MDIO(O)
ETH_MDIO(I)
t
MDC
t
d(MDIO)
t
su(MDIO)
t
h(MDIO)
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RMII_REF_CLK
RMII_TX_EN
RMII_TXD[1:0]
RMII_RXD[1:0]
RMII_CRS_DV
t
d(TXEN)
t
d(TXD)
t
su(RXD)
t
su(CRS)
t
ih(RXD)
t
ih(CRS)
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