test_lucas_com.c

Linux下面的串口驱动程序

#include<stdio.h>
#include<sys/types.h>
#include<sys/stat.h>
#include<fcntl.h>
#include<string.h>
void show_usage(char* argv);
const char* DEV_NAME="/dev/lucas_com0";

int main(int argc, char** argv)
{
	int times=2;	
	char ch;	
	int i;
	int fd;
	int rd_bytes,wr_bytes;
	char buf[3]={'?','?','?'};
	char one_byte=0;
	if(2!=argc)
	{
		show_usage(argv[0]);	
	}
	
	fd=open(DEV_NAME,O_RDWR,0777);
	printf("fd=%d\n",fd);
	if(0==strcmp(argv[1],"-w"))
	{
		buf[0]='a';buf[1]='b';buf[2]='c';
		wr_bytes=write(fd,buf,sizeof(buf));
		printf("%d bytes written\n",wr_bytes);
	}
	else if(0==strcmp(argv[1],"-r"))
	{
		printf("address of buf:%llu\n",buf);
		do{		
		
			rd_bytes=read(fd,buf,sizeof(buf));
			//printf("%d bytes read\n",rd_bytes);			
			printf("buf[0]=%c\n",buf[0]);
			for(i=0;i<rd_bytes;i++)
			{
				printf("buf[%d]=%d\n",i,buf[i]);	
			}
			printf("press q to quit\n");
		}while('q'!=getchar());
	}
	else if(0==strcmp(argv[1],"-i"))
	{
		printf("address of buf:%llu\n",buf);
		printf("press q to quit read, press other keys to read once\n");
		while(1)
		{
			scanf("%c",&ch);
			if('q'==ch)	break;
					
			rd_bytes=read(fd,buf,sizeof(buf));
			printf("%d bytes read\n",rd_bytes);			
			for(i=0;i<rd_bytes;i++)
			{
				printf("buf[%d]=%c\n",i,buf[i]);	
			}
		}
	}
	else
	{
		close(fd);
		show_usage(argv[0]);
		
	}
	
	close(fd);
	return 0;
}
void show_usage(char* argv)
{
	
	printf("usage: %s [-r|-w|-i]\n",argv);
	exit(0);
}