Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Keil/AT32F437xx_v2/ETHERNET_MAC/MACMIIADDR#0x0
Ethernet MAC MII address register
MII busy
MII write
Clock range
MII register
PHY address
https://github.com/cmsis-svd/cmsis-svd-data