3.26 GPIO Basics
[!IMPORTANT] This page is intended for the Seeed
reComputer J401carrier-board family, such asreComputer J4012. The 40-pin header layout and pin behavior are board-specific and should not be assumed to match other Jetson carrier boards.
Introduction
GPIO stands for General Purpose Input/Output. These pins let software read external digital signals or drive simple peripherals such as LEDs, buttons, buzzers, and control lines.
Numbering Modes
The Jetson.GPIO library supports two common numbering schemes:
| Mode | Description | Typical Use |
|---|---|---|
BOARD | Numbers pins by their physical location on the 40-pin header | Best when you are wiring directly from the header silkscreen or a pinout diagram |
BCM | Numbers pins by the GPIO mapping used by the library | Best when you are following Python GPIO examples that refer to logical GPIO IDs |
GPIO.BOARD Layout
GPIO.BCM Layout
Example Pin Reference
The image below shows an additional pin-reference example that is useful before testing input or output functions.
