Datasheet

STM32F051x Functional overview
Doc ID 022265 Rev 3 15/105
Several prescalers allow the application to configure the frequency of the AHB and the APB
domains. The maximum frequency of the AHB and the APB domains is 48 MHz.
Figure 2. Clock tree
3.7 General-purpose inputs/outputs (GPIOs)
Each of the GPIO pins can be configured by software as output (push-pull or open-drain), as
input (with or without pull-up or pull-down) or as peripheral alternate function. Most of the
GPIO pins are shared with digital or analog alternate functions.
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