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Problem With Ethernet RMII Module Infinite SoftwareReset Loop

Question asked by jones.david.009 on Sep 19, 2015
Latest reply on Sep 20, 2015 by jones.david.009
Hello to All

I am Working on a RMII Module With DP83848v.I use Stm32f4xg Eval Board Schematic to Design this board.(you can download it in st site that you knew it better than me)
i noticed that St design Ethernet that can be used as MII and RMII So i copied this Schematic to my Project(with just chnaging resistor as single resistor not Package Resistor).
I assembled it in RMII Config and found that it's not Working
i compare it to THIS SCHEMATIC from waveshare and found that pin39 in phy is connected to RX_DV_MII/CRS_DV_RMII Which is Wrong i think because in RMII CRS_DV Located in pin40.(please tell me if i'm wrong)so i cut tracks on my board and repair my board just like Waveshare's Board.

i connect my ethernet module to a Stm32f429IIT Board and Connect Pins like below

PA1--->MII_RX_CLK/RMII_REF_CLK
PA2--->MII_MDIO
PA7--->MII_CRS
PC1--->MII_MDC
PC4--->MII_RXD0
PC5--->MII_RXD1
PG11--->MII_TXEN
PG13--->MII_TXD0
PG14--->MII_TXD1

i test module with this Project
this project is by default RMII and i test it in another project that worked correctly and i just checked pin Configuration in GPIO_Config method.

i executed project and in debug mode i see it is in an indefinite loop software reset. i checked 50MHZ MAC to phy oscilator in both end and they are OK.

i replaced 10MHZ oscilator with a 8MHZ crystal(with changing programm)
i used mxcube and the same result occured.
i guess that long distance between ethernet module and MCU module causes problem but i'm not sure about it because 50MHZ is not a high frequency.


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