APB1 peripheral clocks enable in Sleep mode register 1
| TIM2SMEN | TIM2 timer clock enable during CPU1 CSleep mode. |
| RTCAPBSMEN | RTC bus clock enable during CPU1 CSleep mode. |
| WWDGSMEN | Window watchdog clocks enable during CPU1 CSleep mode. |
| SPI2S2SMEN | SPI2S2 clock enable during CPU1 CSleep mode. |
| USART2SMEN | USART2 clock enable during CPU1 CSleep mode. |
| I2C1SMEN | I2C1 clock enable during CPU1 Csleep and CStop modes |
| I2C2SMEN | I2C2 clock enable during CPU1 Csleep and CStop modes |
| I2C3SMEN | I2C3 clock enable during CPU1 Csleep and CStop modes |
| DACSMEN | DAC1 clock enable during CPU1 CSleep mode. |
| LPTIM1SMEN | Low power timer 1 clock enable during CPU1 Csleep and CStop mode |