Dear All, In concrete, we target 3 registers from RCC: GPIO_AHBENR, APB1ENR, and APB2ENR https://github.com/Ell-i/Runtime/blob/master/stm32/cores/arduelli/arduelli_gpio.h#L107 https://github.com/Ell-i/Runtime/blob/master/stm32/cores/arduelli/arduelli_usart.h#L71 https://github.com/Ell-i/Runtime/blob/master/stm32/cores/arduelli/arduelli_timer.h#L70 However, we generate a initialisation register for each enabled peripheral, leading to 15 initialisation registers in the case of the stm32f334 (with usart activated): 4 for gpio, 8 for timer, and 3 for usart, instead of only 3. I propose to use a similar alternative to the one we use for the GPIOs, where we generate the final state of the registers by collecting the variables and ORing them: https://github.com/Ell-i/Runtime/blob/master/stm32/cores/arduelli/arduelli_gpio.h#L154 I have one concrete question before proceeding: Is it necessary to activate the peripherals one by one (for power stability, maybe)?, or, in other words, is there any problem if all the peripherals required for each register are activated at once? With Warm Regards, Ivan Raul