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Can STM32F207xx Generate 50MHz Clock for RMII Ethernet PHY ?

Question asked by mai-au on Aug 29, 2013
Latest reply on Jul 29, 2015 by H.Rick

With regard to the STM32F207ZET, on Page 30 of the current STM32F207xxx Datasheet (Doc ID 15818 Rev 9 Oct 2012) it says "...the PHY is connected to the STM32F207xx MII port using 17 signals for MII or 9 signals for RMII, and can be clocked using the 25 MHz (MII) or 50 MHz (RMII) output from the STM32F207xx".

I understand this means the STM32F207xx can provide the 50MHz clock required by a PHY circuit operating in RMII mode.  But I can find no further reference to this, such as any details of how the STM32F207xx must be configured to enable this, or even which pin the 50MHz RMII Clock Signal will be output on.  However, on page 164 of the same datasheet the 50MHz signal is shown being provided by a seperate crystal oscillator.

So, is it possible to have the STM32F207xx provide the 50MHz Clock Signal required for a RMII PHY, or is the datasheet incorrect on Page 30 ?

If it is possible to have the STM32F207xx provide the 50MHz Clock Signal required for the RMII PHY, what documentation describes how to make use of this ?

Thanking you,

mai-au.

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