ao_arch_block_interrupts();
+ /* Enable power interface clock */
+ stm_rcc.apb1enr |= (1 << STM_RCC_APB1ENR_PWREN);
+ ao_arch_nop();
stm_scb.scr |= (1 << STM_SCB_SCR_SLEEPDEEP);
ao_arch_nop();
stm_pwr.cr |= (1 << STM_PWR_CR_PDDS) | (1 << STM_PWR_CR_LPDS);