GPIOs are used in:
- Devices with pin scarcity: integrated circuits such as system-on-a-chip, embedded and custom hardware, and programmable logic devices (for example, FPGAs)
- Multifunction chips: power managers, audio codecs, and video cards
- Embedded applications (for example, Arduino, BeagleBone, PSoC kits and Raspberry Pi) make heavy use of GPIO for reading from various environmental sensors (IR, video, temperature, 3-axis orientation, and acceleration), and for writing output to DC motors (via PWM), audio, LCD displays, or LEDs for status.
