前面的方法可以參照（一）來配置GPIO口。

下面是代碼。。。僅供參考，轉載請註明出處。

1. 先輸入以下指令，再復制代碼，Ctrl+X 輸入Y 回車 保存。

sudo nano start.c

#include "car.h"
#include <stdio.h>
#include <stdlib.h>
#include <wiringPi.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in
 
.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#define IN1 0    // wiringPi GPIO0(pin11)   car.GPIO
#define IN2 1
#define IN3 2
#define IN4 3
#define IN5 4  //Ultrasound module.GPIO   send
#define IN6 5  //                         accept
 

/*   Write By ITJoker
      Time:2.18.2.4
      Version:1.0
*/
int up()
{
  wiringPiSetup() ;
  pinMode (IN1, OUTPUT) ;
  pinMode (IN2, OUTPUT) ;
  pinMode (IN3, OUTPUT) ;
  pinMode (IN4, OUTPUT) ;
  digitalWrite(IN1, HIGH) ; delay (500) ;
  digitalWrite(IN2,  LOW) ; delay (500) ;
  digitalWrite(IN3, HIGH) ; delay (
 
500) ;
  digitalWrite(IN4,  LOW) ; delay (500) ;
}
int down()
{
  wiringPiSetup() ;
  pinMode (IN1, OUTPUT) ;
  pinMode (IN2, OUTPUT) ;
  pinMode (IN3, OUTPUT) ;
  pinMode (IN4, OUTPUT) ;
  digitalWrite(IN1,  LOW) ; delay (500) ;
  digitalWrite(IN2, HIGH) ; delay (500) ;
  digitalWrite(IN3,  LOW) ; delay (500) ;
  digitalWrite(IN4, HIGH) ; delay (500) ;
}
int right()
{
  wiringPiSetup() ;
  pinMode (IN1, OUTPUT) ;
  pinMode (IN2, OUTPUT) ;
  pinMode (IN3, OUTPUT) ;
  pinMode (IN4, OUTPUT) ;
  digitalWrite(IN1,  LOW) ; delay (500) ;
  digitalWrite(IN2, HIGH) ; delay (500) ;
  digitalWrite(IN3, HIGH) ; delay (500) ;
  digitalWrite(IN4,  LOW) ; delay (500) ;
}
int left()
{
  wiringPiSetup() ;
  pinMode (IN1, OUTPUT) ;
  pinMode (IN2, OUTPUT) ;
  pinMode (IN3, OUTPUT) ;
  pinMode (IN4, OUTPUT) ;
  digitalWrite(IN1, HIGH) ; delay (500) ;
  digitalWrite(IN2,  LOW) ; delay (500) ;
  digitalWrite(IN3,  LOW) ; delay (500) ;
  digitalWrite(IN4, HIGH) ; delay (500) ;
}
int stop()
{
  wiringPiSetup() ;
  pinMode (IN1, OUTPUT) ;
  pinMode (IN2, OUTPUT) ;
  pinMode (IN3, OUTPUT) ;
  pinMode (IN4, OUTPUT) ;
  digitalWrite(IN1,  LOW) ; delay (500) ;
  digitalWrite(IN2,  LOW) ; delay (500) ;
  digitalWrite(IN3,  LOW) ; delay (500) ;
  digitalWrite(IN4,  LOW) ; delay (500) ;
}
int main(int argc, char *argv[])
{
    int fd, new_fd, struct_len, numbytes,i;
    struct sockaddr_in server_addr;
    struct sockaddr_in client_addr;
    char buff[BUFSIZ];
    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(8888);//port    8888
    server_addr.sin_addr.s_addr = INADDR_ANY;
    bzero(&(server_addr.sin_zero), 8);
    struct_len = sizeof(struct sockaddr_in);

    fd = socket(AF_INET, SOCK_STREAM, 0);
    while(bind(fd, (struct sockaddr *)&server_addr, struct_len) == -1);
    printf("Bind Success!\n");
    while(listen(fd, 10) == -1);
    printf("Listening....\n");
    printf("Ready for Accept,Waitting...\n");
    new_fd = accept(fd, (struct sockaddr *)&client_addr, &struct_len);
    printf("Get the Client.\n");
    // numbytes = send(new_fd,"Welcome to my server\n",21,0);
    while((numbytes = recv(new_fd, buff, BUFSIZ, 0)) > 0)
    {
        buff[numbytes] = ‘\0‘;
        printf("%s\n",buff);
            if(send(new_fd,buff,numbytes,0)<0)
            {
                perror("write");
                return 1;
            }
        //txtz=find(buff,sizeof(buff),‘u‘)
        //strcmp(buff,‘u‘)==0
        if(buff[0]==‘u‘)
          up();
        else if(buff[0]==‘d‘)
          down();
        else if(buff[0]==‘r‘)
          right();
        else if(buff[0]==‘l‘)
          left();
        else if(buff[0]==‘s‘)
          stop();
    }
    close(new_fd);
    close(fd);
    return 0;
}

2.為了編寫方便，建立makedile。

sudo nano makefile

編寫內容如下：

start:start.o  
 gcc start.c -o start -lwiringPi  
clean:  
 rm -f start start.o

3.最後 輸入指令：

make

樹莓派小車By 樹莓派愛好者ITJoker（通過C socket通信實現樹莓派視頻小車）（二）