通过Raspberry Pi(树莓派)的GPIO接口控制发光二极管

原文：http://www.codelast.com/?p=5155

参考：http://blog.csdn.net/liang890319/article/details/8643069

下载安装包，解压，编译，安装：

mkdir temp
cd temp
wget http://project-downloads.drogon.net/files/wiringPi.tgz
tar xf wiringPi.tgz
cd wiringPi/wiringPi/
make
make install

③下面写程序测试：

// led.c
 
#include <wiringPi.h>
#include <stdio.h>
#include <stdlib.h>
 
int main (int argc,char* argv[])
{
  if (argc < 2) {
    printf("Usage example: ./led 4 \n");
    return 1;
  }
  int pinNumber = atoi(argv[1]);
 
  if (-1 == wiringPiSetup()) {
    printf("Setup wiringPi failed!");
    return 1;
  }
 
  pinMode(pinNumber, OUTPUT); // set mode to output 
  while(1) {
    digitalWrite(pinNumber, 1); // output a high level 
    delay(800);
    digitalWrite(pinNumber, 0); // output a low level 
    delay(800);
  }
 
  return 0;
}

编译程序：

gcc led.c -o led -lwiringPi

运行程序：
Run the program:

./led 4

可以看到LED开始闪烁了

可能遇见的问题：

GPIO测试编译时出现了这个问题

/usr/lib/gcc/arm-linux-gnueabi/4.6/http://www.cnblogs.com/../libwiringPi.so:undefined reference to `i2c_smbus_write_byte'
/usr/lib/gcc/arm-linux-gnueabi/4.6/http://www.cnblogs.com/../libwiringPi.so:undefined reference to `i2c_smbus_read_byte'
/usr/lib/gcc/arm-linux-gnueabi/4.6/http://www.cnblogs.com/../libwiringPi.so:undefined reference to `i2c_smbus_write_byte_data'
/usr/lib/gcc/arm-linux-gnueabi/4.6/http://www.cnblogs.com/../libwiringPi.so:undefined reference to `i2c_smbus_write_word_data'
/usr/lib/gcc/arm-linux-gnueabi/4.6/http://www.cnblogs.com/../libwiringPi.so:undefined reference to `i2c_smbus_read_word_data'
/usr/lib/gcc/arm-linux-gnueabi/4.6/http://www.cnblogs.com/../libwiringPi.so:undefined reference to `i2c_smbus_read_byte_data'
collect2: ld returned 1 exit status

 

官方论坛上说是少装了库的原因

安装这几个库： i2c-tools，libi2c-dev ，python-smbus

安装参考 sudo apt-get install libi2c-dev

然后重新

make clean

sudo make uninstall

 

make

sudo make install

重新编译下你的.c文件

gcc led.c -o led -lwiringPi

sudo ./led 4

虽然输入的是4

实际上是GPIO23不停输出高低电平