General-purpose input/output

A general-purpose input/output (GPIO) is an uncommitted digital signal pin on an integrated circuit or electronic circuit (e.g. MCUs/MPUs) board which may be used as an input or output, or both, and is controllable by software.

GPIOs have no predefined purpose and are unused by default.^[1]^[2] If used, the purpose and behavior of a GPIO is defined and implemented by the designer of higher assembly-level circuitry: the circuit board designer in the case of integrated circuit GPIOs, or system integrator in the case of board-level GPIOs.

^ White, Jon, ed. (2016). Raspberry Pi – The Complete Manual (7th ed.). Bournemouth, England, United Kingdom: Imagine Publishing. p. 36. ISBN 978-1785463709.
^ "General Purpose Input/Output". Oracle Java ME Embedded Developer's Guide (8 ed.). Oracle Corporation. 2014.

[1] White, Jon, ed. (2016). Raspberry Pi – The Complete Manual (7th ed.). Bournemouth, England, United Kingdom: Imagine Publishing. p. 36. ISBN 978-1785463709.

[:0-2] "General Purpose Input/Output". Oracle Java ME Embedded Developer's Guide (8 ed.). Oracle Corporation. 2014.

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