Inputs and outputs (I/O) are the peripherals through which the digital core of a microcontroller talks to the physical world: reading a sensor, driving an actuator, communicating with another chip. Without them, the processor would compute without ever acting or perceiving.
What forms does it take?
I/O covers the logic pins (on/off), analog-to-digital conversion (reading a voltage), PWM signal generation (dosing a command) and the communication buses (UART, I2C, SPI) for exchanging structured data. The converter the other way round (the DAC, which produces a real analog voltage) is rarer: PWM, direct or filtered, stands in for it in most cases.
See also
- Microcontroller — the chip that integrates the I/O peripherals
- GPIO — the logic input and output pins
- Communication buses — the I/O dedicated to exchanging data
- Interrupt — reacting to an input without polling it in a loop