打开设备

TTL下载器插在USB接口上，在终端输入“ls/dev/tty”

代码如下：

 1 # include <stdio.h>
 2 # include <assert.h>                        //测试函数
 3 # include <string.h>        
 4 # include "Picustom.h"                        //自定义头文件
 5 # define uint8 unsigned char                //宏定义
 6 # define N 124
 7 
 8 struct serial_port{
 9     char device[32];                          //设备路径
10     unsigned long baud;                      //波特率
11     int fd;                                 //设备描述符
12     unsigned char dates[1024];              //文件转存
13     unsigned char temp;                     //字符缓存
14     int len;                                //长度
15 };
16 
17 //字符串cp函数
18 char * my_strcpy(char *dest, const char *src){    //将源字符串加const，表明其为输入参数,起到相应的保护作用  
19    assert(src != NULL&&dest != NULL);            //对源地址和目的地址加非0断言  
20    char *ret = dest;  
21    while ((*dest++ = *src++));
22     return ret;                                    //引用返回地址，方便链式操作！！  
23 }
24 //清空serial
25 int clean_serial_port(struct serial_port *serial){
26     memset(serial->dates,0,1024);
27     serial->len = 0;
28     printf("\n");
29     return 0;
30 }
31 //字段尾部加0
32 int set_serial_dates_end(struct serial_port *serial){
33     if('\n' == serial->temp){    
34         printf("\n");
35         serial->dates[serial->len--]='\0';
36     }
37     return 0;
38 }
39 
40 //打印调试
41 int printf_serial_dates(struct serial_port *serial){
42     int i = 0;
43     if('\n' == serial->temp){
44         for(i = 0;i<=serial->len;i++){
45             printf(" %d---%x",i,serial->dates[i]);
46         }
47     }
48     return 0;
49 }
50 
51 //读取完成清空缓存0
52 int clean_serial(struct serial_port *serial){
53     if('\n' == serial->temp){        
54         clean_serial_port(serial);
55     }
56     return 0;
57 }
58 
59 
60 int main(void){
61     struct serial_port serial;
62     wiringPi(0,0);                                      //wiringPi初始化
63     serial.fd = init_serial_port("/dev/ttyUSB0",9600);    //通过树莓派函数打开
64     while(1){
65         serial.temp = Serial_data_read_char_10(serial.fd);
66         printf("%x\t",serial.temp);
67         if(((0xff > serial.temp)&&(0x80 < serial.temp))||(serial.temp == '\r')||(serial.temp == '\n')){
68             serial.dates[serial.len++] = serial.temp;
69             set_serial_dates_end(&serial);        //尾部加0
70             //printf_serial_dates(&serial);        //打印
71         
72         clean_serial(&serial);                    //读取完成清空缓存0
73         }
74         else{                                    //出错清空缓存
75         clean_serial_port(&serial);
76         }
77     }
78     return 0;
79 }