PLL configuration register
| PLLM | Division factor for the main PLL (PLL) and audio PLL (PLLI2S) input clock |
| PLLN | Main PLL (PLL) multiplication factor for VCO |
| PLLP | Main PLL (PLL) division factor for main system clock |
| PLLSRC | Main PLL(PLL) and audio PLL (PLLI2S) entry clock source |
| PLLQ | Main PLL (PLL) division factor for USB OTG FS, SDIO and random number generator clocks |
| PLLR | Main PLL division factor for DSI clock |