General-purpose input/output - Wikipedia
https://en.wikipedia.org/wiki/General-purpose_input/output
A general-purpose input/output (GPIO) is an uncommitted digital signal pin on an integrated circuit or electronic circuit board which may be used as an input or output, or both, and is controllable by the user at runtime. GPIOs have no predefined purpose and are unused by default.
GPIO - Raspberry Pi Documentation
https://www.raspberrypi.org/documentation/usage/gpio/
The remaining pins are all general purpose 3V3 pins, meaning outputs are set to 3V3 and inputs A GPIO pin designated as an input pin can be read as high (3V3) or low (0V). This is made easier with...
GPIO - eLinux.org
https://elinux.org/GPIO
General Purpose Input or Output: a generic I/O line on a SoC is often referred to as a GPIO. By definition a GPIO is a line that can be used as an input or output. In some cases vendors will to a signal that support external interrupts as a GPIO line as well...
gpio - Gateworks
http://trac.gateworks.com/wiki/gpio
Gateworks boards use General Purpose Input / Output (GPIO) pins commonly for things such as: enabling/disabling of devices (ie serial drivers). signal steering (ie steer USB bus between...
GPIO Mappings — The Linux Kernel documentation
https://www.kernel.org/doc/html/latest/driver-api/gpio/board.html
GPIO Mappings¶. This document explains how GPIOs can be assigned to given devices and functions. Note that it only applies to the new descriptor-based interface.
gpio - NodeMCU Documentation
https://nodemcu.readthedocs.io/en/release/modules/gpio/
This module provides access to the GPIO (General Purpose Input/Output) subsystem. If not using a NodeMCU dev kit, please refer to the below GPIO pin maps for the index↔gpio mapping.
GPIO Programming: Using the sysfs Interface | ICS
https://www.ics.com/blog/gpio-programming-using-sysfs-interface
GPIO devices appear as part of sysfs. Before we continue, I should mention that this interface is being deprecated in favor of a new GPIO character device API. The new API addresses a number of issues...
An Introduction to chardev GPIO and Libgpiod on the Raspberry PI...
https://www.beyondlogic.org/an-introduction-to-chardev-gpio-and-libgpiod-on-the-raspberry-pi/
Libgpiod (Library General Purpose Input/Output device) provides both API calls for use in your own programs and the following six user-mode applications to manipulate GPIO lines