GPIO (General Purpose Input/Output)
Configurable digital pins on a microcontroller or SBC (Single Board Computer) that can be set as input or output in software.
On Raspberry Pi / reTerminal:
- 40 pins total
- Logic level: 3.3V (outputs HIGH = 3.3V; inputs are 3.3V-tolerant)
- Max current: 16mA per pin, ~50mA total for all GPIO
- No native ADC — use Grove Base Hat for analog
Protocols available on GPIO pins: PWM, SPI, I2C, UART, PCM
Python library: GPIO Zero (from gpiozero import LED, Button, PWMLED, Servo)
See Also
- GPIO and reTerminal topic
- ADC concept