RCC APB2 Clock Register
| TIM1EN | TIM1 peripheral clock enable |
| TIM8EN | TIM8 peripheral clock enable |
| USART1EN | USART1 Peripheral Clocks Enable |
| USART6EN | USART6 Peripheral Clocks Enable |
| UART9EN | UART9 peripheral clocks enable Set and reset by software. The peripheral clocks of the UART9 are the kernel clock selected by USART16910SEL and provided to UCKL input, and the rcc_pclk2 bus interface clock. |
| USART10EN | USART10 peripheral clocks enable Set and reset by software. The peripheral clocks of the USART10 are the kernel clock selected by USART16910SEL and provided to UCKL input, and the rcc_pclk2 bus interface clock. |
| SPI1EN | SPI1 Peripheral Clocks Enable |
| SPI4EN | SPI4 Peripheral Clocks Enable |
| TIM15EN | TIM15 peripheral clock enable Set and reset by software. |
| TIM16EN | TIM16 peripheral clock enable |
| TIM17EN | TIM17 peripheral clock enable |
| SPI5EN | SPI5 Peripheral Clocks Enable |
| SAI1EN | SAI1 Peripheral Clocks Enable |
| DFSDM1EN | DFSDM1 peripheral clocks enable Set and reset by software. DFSDM1 peripheral clocks are the kernel clocks selected by SAI1SEL and DFSDM1SEL and provided to Aclk and clk inputs respectively, |