常规流程

按照jetson-gpio的README即可简单完成

安装Jetson.GPIO库
1
sudo pip install Jetson.GPIO

设置用户权限

1 2	sudo groupadd -f -r gpio sudo usermod -a -G gpio {your_user_name}

运行示例程序jetson-gpio/samples，如

import Jetson.GPIO as GPIO
import time

# Pin Definitions
output_pin = 18  # BCM pin 18, BOARD pin 12

def main():
    # Pin Setup:
    GPIO.setmode(GPIO.BCM)  # BCM pin-numbering scheme from Raspberry Pi
    # set pin as an output pin with optional initial state of HIGH
    GPIO.setup(output_pin, GPIO.OUT, initial=GPIO.HIGH)

    print("Starting demo now! Press CTRL+C to exit")
    curr_value = GPIO.HIGH
    try:
        while True:
            time.sleep(1)
            # Toggle the output every second
            print("Outputting {} to pin {}".format(curr_value, output_pin))
            GPIO.output(output_pin, curr_value)
            curr_value ^= GPIO.HIGH
    finally:
        GPIO.cleanup()

if __name__ == '__main__':
    main()

Jetson GPIO库提供了四种给I / O引脚编号的方法（GPIO.setmode）

BOARD：物理引脚编号（40针接口顺序）

BCM：Broadcom SoC 的 GPIO 编号

CVM：CVM/CVB 连接器的信号名称

TEGRA_SOC：Tegra SoC 信号名称

查询Jeston型号
1
cat /proc/device-tree/model
1
NVIDIA Jetson Orin NX Engineering Reference Developer Kit Super
查看Jetpack版本
1
jtop
右上角显示版本Jetpack 6.2 L4T 36.4.3

一般到这里你就可以根据引脚定义图愉快地开始控制了，但如果你的Jetpack版本大于等于6.2的话，你会发现无论如何也无法切换到输出模式输出高电平或者低电平

6.0>=Jetpack版本<6.2.2

由于下游内核驱动的变动，现在上层软件不能直接切换GPIO模式，所以要通过busybox更改引脚复用器，在Jetson Orin NX引脚表格中可以看到很多GPIO的默认模式是Input，所以需要进行修改

更新Jetson.GPIO
1
pip install -U Jetson.GPIO
2.1.7版本没有jetson-gpio-pinmux-lookup工具所以要更新，我更新到2.1.12版本就有了

使用Pinmux 查找工具可以快速查询到寄存器地址，如简单直观的引脚定义图或下图所示

比如我要让GPIO09也就是7号针脚改为输出控制，

$ jetson-gpio-pinmux-lookup 7
WARNING: Carrier board is not from a Jetson Developer Kit.
WARNNIG: Jetson.GPIO library has not been verified with this carrier board,
WARNING: and in fact is unlikely to work correctly.
WARNING: Carrier board is not from a Jetson Developer Kit.
WARNNIG: Jetson.GPIO library has not been verified with this carrier board,
WARNING: and in fact is unlikely to work correctly.
GPIO Pin 7: Mux Register Address = 0x2448030

查询到地址为0x2448030，使用devmem工具查看寄存器值

# 一台Jetson
$ sudo busybox devmem 0x02448030
0x0000005A
# 另一台Jetson
$ sudo busybox devmem 0x02448030
0x0000045A

使用devmem工具设置寄存器

1 2	# gpio09 板载7号 sudo busybox devmem 0x02448030 w 0x004

比如还有GPIO11也就是31号针脚

# 查询寄存器地址
$ jetson-gpio-pinmux-lookup 31
WARNING: Carrier board is not from a Jetson Developer Kit.
WARNNIG: Jetson.GPIO library has not been verified with this carrier board,
WARNING: and in fact is unlikely to work correctly.
WARNING: Carrier board is not from a Jetson Developer Kit.
WARNNIG: Jetson.GPIO library has not been verified with this carrier board,
WARNING: and in fact is unlikely to work correctly.
GPIO Pin 31: Mux Register Address = 0x2430070
# 查询寄存器的值
$ sudo busybox devmem 0x02430070
0x00000058
# 修改寄存器的值 goio11 板载31号
$ sudo busybox devmem 0x02430070 w 0x004