CCIPR1
| USART1SEL | USART1 clock source selection |
| USART2SEL | USART2 clock source selection |
| USART3SEL | USART3 clock source selection |
| UART4SEL | UART4 clock source selection |
| UART5SEL | UART5 clock source selection |
| LPUART1SEL | LPUART1 clock source selection |
| I2C1SEL | I2C1 clock source selection |
| I2C2SEL | I2C2 clock source selection |
| I2C3SEL | I2C3 clock source selection |
| LPTIM1SEL | Low power timer 1 clock source selection |
| LPTIM2SEL | Low power timer 2 clock source selection |
| LPTIM3SEL | Low-power timer 3 clock source selection |
| FDCANSEL | FDCAN clock source selection |
| CLK48MSEL | 48 MHz clock source selection |
| ADCSEL | ADCs clock source selection |