Power control register 3
| EWUP1 | Enable Wakeup pin WKUP1  |  
| EWUP2 | Enable Wakeup pin WKUP2  |  
| EWUP3 | Enable Wakeup pin WKUP3  |  
| EWUP4 | Enable Wakeup pin WKUP4  |  
| EWUP5 | Enable WKUP5 wakeup pin  |  
| EWUP6 | Enable WKUP6 wakeup pin  |  
| RRS | SRAM retention in Standby mode  |  
| ENB_ULP | Ultra-low-power enable  |  
| APC | Apply pull-up and pull-down configuration  |  
| EIWUL | Enable internal wakeup line  |