RCC AHB3 Clock Register
| MDMAEN | MDMA Peripheral Clock Enable |
| DMA2DEN | DMA2D Peripheral Clock Enable |
| FMCEN | FMC Peripheral Clocks Enable |
| OCTOSPI1EN | OCTOSPI1 and OCTOSPI1 delay clock enable |
| SDMMC1EN | SDMMC1 and SDMMC1 Delay Clock Enable |
| OCTOSPI2EN | OCTOSPI2 clock enable Set and reset by software. |
| IOMNGREN | OCTOSPIM clock enable Set and reset by software. |
| OTFD1EN | OTFD1 clock enable Set and reset by software. |
| OTFD2EN | OTFD2 clock enable Set and reset by software. |