3. General purpose inputs/outputs(GPIOs)ΒΆ

Each of the GPIO pins can be configured by software as output (with pull-up or pull-down), as input (with pull-up or pull-down) or as peripheral alternate function. Most of the GPIO pins are shared with digital or analog alternate functions. All GPIOs are high-current-capable and have speed selection to better manage internal noise, power consumption. In general, it has the following features:

  1. Control GPIO input/output direction by using direction register

  2. Internal pull-up/pull-down resistor by using pull-up/pull-down resistor control register

  3. Select suitable output driving current capability