STM32H723VG没有外置PHY，使用内置PHY实现usb通讯

使用FS 可以用内置PHY

使用HS需要外置PHY


The OTG_HS interface general features are the following:
•      It is USB-IF certified to the Universal Serial Bus Specification Rev 2.0
•      OTG_HS supports the following PHY interfaces:
–     An on-chip full-speed PHY
–     A ULPI interface for external high-speed PHY