Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32F107xx/ETHERNET_MAC/MACMIIAR#0x0
Ethernet MAC MII address register (ETH_MACMIIAR)
MII busy
MII write
Clock range
MII register
PHY address
https://github.com/cmsis-svd/cmsis-svd-data