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STM32F4 Ethernet PHY connection(MII_CRS pin Issue)

Jin Kim
Associate
Posted on January 09, 2018 at 07:16

Hi Everybody Help me.

I want to use it in the following way.

0690X0000060PGjQAM.gif

However, Ethernet PHY chip does not have MII_CRS pins. (PHY Chip is RTL8304E)

Do you have to handle the MII_CRS pin of STM32F4?

The MCU Ref. Manual notes:

''MII_CRS: carrier sense is asserted by the PHY when either the transmit or receive

medium is non idle. It shall be deasserted by the PHY when both the transmit and

receive media are idle. The PHY must ensure that the MII_CS signal remains asserted

throughout the duration of a collision condition. This signal is not required to transition

synchronously with respect to the TX and RX clocks. In full duplex mode the state of

this signal is don’t care for the MAC sublayer.''

I can not tell what to do with this pin.

1) full up

2) full dwon

3) RX_DV pin and MII_CRS pinsCommon connection

Please let me know

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