»pigpio« is a C library for controlling RaspberryPi GPIOs


pigpio is a C library for the Raspberry which allows control of the General Purpose Input Outputs (GPIO).


  • Sampling and time-stamping of GPIO 0-31 between 100,000 and 1,000,000 times per second
  • Provision of PWM on any number of the user GPIO simultaneously
  • Provision of servo pulses on any number of the user GPIO simultaneously
  • Callbacks when any of GPIO 0-31 change state (callbacks receive the time of the event
    accurate to a few microseconds)
  • Notifications via pipe when any of GPIO 0-31 change state
  • Callbacks at timed intervals
  • Reading/writing all of the GPIO in a bank (0-31, 32-53) as a single operation
  • Individually setting GPIO modes, reading and writing
  • Socket and pipe interfaces for the bulk of the functionality in addition to the
    underlying C library calls
  • Construction of arbitrary waveforms to give precise timing of output GPIO
    level changes (accurate to a few microseconds)
  • Software serial links, I2C, and SPI using any user GPIO
  • Rudimentary permission control through the socket and pipe interfaces so users
    can be prevented from “updating” inappropriate GPIO
  • Creating and running scripts on the pigpio daemon


The library provides a number of control interfaces

  • the C function interface,
  • the /dev/pigpio pipe interface,
  • the socket interface (used by the pigs utility and the Python module).


A number of utility programs are provided:

  • the pigpiod daemon,
  • the Python module,
  • the piscope digital waveform viewer,
  • the pigs command line utility,
  • the pig2vcd utility which converts notifications into the value change dump (VCD)
    format (useful for viewing digital waveforms with GTKWave).


Enjoy the main homepage at pigpio library with many usage examples.