wiringPi 是树梅派上操作 GPIO 的一个库。其官网：wiringpi.com/
下面简要介绍下 wiringPi 的安装及使用
安装
获取并安装最新版本
cd /tmp
wget https://project-downloads.drogon.net/wiringpi-latest.deb
sudo dpkg -i wiringpi-latest.deb
检查下是否安装成功
$ gpio -v
gpio version: 2.52
Copyright (c) 2012-2018 Gordon Henderson
This is free software with ABSOLUTELY NO WARRANTY.
For details type: gpio -warranty
gpio 命令使用
gpio readall 查看接口状态，表格方式输出
-> % gpio readall
+-----+-----+---------+------+---+---Pi 2---+---+------+---------+-----+-----+
| BCM | wPi | Name | Mode | V | Physical | V | Mode | Name | wPi | BCM |
+-----+-----+---------+------+---+----++----+---+------+---------+-----+-----+
| | | 3.3v | | | 1 || 2 | | | 5v | | |
| 2 | 8 | SDA.1 | IN | 1 | 3 || 4 | | | 5v | | |
| 3 | 9 | SCL.1 | IN | 1 | 5 || 6 | | | 0v | | |
| 4 | 7 | GPIO. 7 | IN | 1 | 7 || 8 | 1 | ALT0 | TxD | 15 | 14 |
| | | 0v | | | 9 || 10 | 1 | ALT0 | RxD | 16 | 15 |
| 17 | 0 | GPIO. 0 | IN | 0 | 11 || 12 | 0 | IN | GPIO. 1 | 1 | 18 |
| 27 | 2 | GPIO. 2 | IN | 0 | 13 || 14 | | | 0v | | |
| 22 | 3 | GPIO. 3 | IN | 0 | 15 || 16 | 0 | OUT | GPIO. 4 | 4 | 23 |
| | | 3.3v | | | 17 || 18 | 0 | OUT | GPIO. 5 | 5 | 24 |
| 10 | 12 | MOSI | IN | 0 | 19 || 20 | | | 0v | | |
| 9 | 13 | MISO | IN | 0 | 21 || 22 | 0 | IN | GPIO. 6 | 6 | 25 |
| 11 | 14 | SCLK | IN | 0 | 23 || 24 | 1 | IN | CE0 | 10 | 8 |
| | | 0v | | | 25 || 26 | 1 | IN | CE1 | 11 | 7 |
| 0 | 30 | SDA.0 | IN | 1 | 27 || 28 | 1 | IN | SCL.0 | 31 | 1 |
| 5 | 21 | GPIO.21 | IN | 1 | 29 || 30 | | | 0v | | |
| 6 | 22 | GPIO.22 | IN | 1 | 31 || 32 | 0 | IN | GPIO.26 | 26 | 12 |
| 13 | 23 | GPIO.23 | IN | 0 | 33 || 34 | | | 0v | | |
| 19 | 24 | GPIO.24 | IN | 0 | 35 || 36 | 0 | IN | GPIO.27 | 27 | 16 |
| 26 | 25 | GPIO.25 | OUT | 1 | 37 || 38 | 0 | IN | GPIO.28 | 28 | 20 |
| | | 0v | | | 39 || 40 | 0 | IN | GPIO.29 | 29 | 21 |
+-----+-----+---------+------+---+----++----+---+------+---------+-----+-----+
| BCM | wPi | Name | Mode | V | Physical | V | Mode | Name | wPi | BCM |
+-----+-----+---------+------+---+---Pi 2---+---+------+---------+-----+-----+
gpio read <pin> 读取指定接口（pin）的逻辑值，输出 0 或 1
gpio write <pin> <value> 设置指定接口（pin）的值（0 或 1），前提是需要接口设为输出模式
gpio mode <pin> <mode> 设置接口（pin）模式（mode）
mode 模式：
input输入模式
output输出模式
pwmPWM 模式
gpio toggle <pin> 更改接口状态，0 -> 1 或 1 -> 0，前提是需要接口设为输出模式
gpio blink <pin> 接口闪烁，通过 Ctrl+C 停止，前提是需要接口设为输出模式
gpio wb <value> 输出一个字节的数据到接口，低位到高位即 GPIO 接口 0-7 号，可以使用 0x 表示十六进制数，接口也需要设置为输出模式
gpio pwm <pin> <value> 输出 PWM 值（0-1023）到指定接口，接口需要设定为 PWM 模式
以上
<pin>皆使用wPi定义的接口号，也可在gpio命令后添加-g参数使用BCM定义的接口号
