gsm_gprs.c

基于LINUX 平台的GPRS通信

/*this is a test about GPRS*/

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include <fcntl.h>	/* open() close() */
#include <unistd.h>	/* read() write()*/

#include <termios.h>	/* set baud rate*/

#include <fcntl.h>
#include <sys/select.h>
#include <sys/time.h>
#include <sys/types.h>

#define FUNC_RUN		0
#define FUNC_NOT_RUN		1

#define SIMPLE_TEST 		1
#define READ_SIM_CARD_ID 	2
#define MAKE_A_CALL 		3
#define WAIT_A_CALL	 		4
#define SHORT_MESSAGE 		5
#define FUNC_QUIT 			6

#define SEND_SHORT_MESSAGE		1
#define READ_SHORT_MESSAGE		2
#define CONFIG_SHORT_MESSAGE_ENV        3
#define QUIT_SHORT_MESSAGE		4

#define DEVICE_TTYS "/dev/ttyS1"
#define MAX_LEN_OF_SHORT_MESSAGE	140

#define RECEIVE_BUF_WAIT_1S 1
#define RECEIVE_BUF_WAIT_2S 2
#define RECEIVE_BUF_WAIT_3S 3
#define RECEIVE_BUF_WAIT_4S 4
#define RECEIVE_BUF_WAIT_5S 5


/*----------------- read datas from GSM/GPRS --------------------------*/
/*succese return 1*/
/*error return 0*/
/*读取串口缓冲区中的数据*/
int read_GSM_GPRS_datas(int fd, char *rcv_buf,int rcv_wait)
{
	int retval;
	fd_set rfds;	/* fd_set 定义 文件描述符集 */
	struct timeval tv;

	int ret,pos;

	tv.tv_sec = rcv_wait;	/* 等待时间 */
	tv.tv_usec = 0;

	pos = 0; /* point to rceeive buf */
	
	while (1)
	{
		FD_ZERO(&rfds);		/* 清除文件描述符集rfds */
		FD_SET(fd, &rfds);	/* 将文件描述符fd 加入到文件描述符集rfds */
		/*使用select函数判断是否接收缓冲区内有数据，
		 如果在等待了([tv.tv_sec]秒+[tv.tv_usec]微秒)后没有数据，
		 则retval=0,出错时 retval=-1,retval其它情况时表示接收到了数据*/

		retval = select(fd+1 , &rfds, NULL, NULL, &tv);
		/* 函数select用于解决I/O复用，成功返回准备好的文件描述符，错误返回’-1’ */
		if (retval == -1) 
		{
			perror("select()");
			break;
		}
		else if (retval) 
		{/*使用read函数读出接收缓冲区中的内容，存放在数组rcv_buf[]中，
			如果接收正确，ret=接收到的字节数*/
			
			ret = read(fd, rcv_buf+pos, 2048); /**ret返回实际读得的字符数*/
			pos += ret;
			if (rcv_buf[pos-2] == '\r' && rcv_buf[pos-1] == '\n') 
			{/*当接收到的字符为‘\r’或者‘\n‘时表示接收了一行数据,
				但并不代表接收数据完成，当接收到以’\r‘’\n‘为结尾的字符串，
				并且再等待了（[tv.tv_sec]秒+[tv.tv_usec]微秒）没有新的数据时，
				认为接收一次数据完成*/
				
				FD_ZERO(&rfds);
				FD_SET(fd, &rfds);

				retval = select(fd+1 , &rfds, NULL, NULL, &tv);

				if (!retval) 
					break;/*没有数据，退出*/
			}
		} 
		else 
		{
			printf("No data\n");
			break;
		}
	}

	return 1;
} /* end read_GSM_GPRS_datas*/



/*------------------ send cmd --------------------------*/
/* succese return 1 */
/* error   return 0 */
/*用于发送数据*/
int send_GSM_GPRS_cmd(int fd, char *send_buf)
{/*将send_buf中的内容发送到fd指向的设备，发送正确
	 ret返回发送的字节数，发送错误ret返回“-1”*/
	
	ssize_t ret;
	
	ret = write(fd,send_buf,strlen(send_buf));
	if (ret == -1)
	{
		printf ("write device %s error\n", DEVICE_TTYS);
		return -1;
	}

	return 1;
} /*end send_GSM_GPRS_cmd*/ 

/*--------------- send cmd and read back result -----------------------*/

void GSM_GPRS_send_cmd_read_result(int fd, char *send_buf, int rcv_wait)
{
	char rcv_buf[2048];
	/*当发送数据为空时，只接收数据;有数据发送时，发送成功后接收*/

	if((send_buf==NULL) || (send_GSM_GPRS_cmd(fd,send_buf)))
	{	/* send success , then read*/
		
		bzero(rcv_buf,sizeof(rcv_buf)); /*清空接收数组*/
		
		if (read_GSM_GPRS_datas(fd,rcv_buf,rcv_wait))
		{	/*成功接收到数据，并打印*/
			printf ("%s\n",rcv_buf);
		}
		else
		{
			printf ("read error\n");
		}
	}
	else
	{
		printf("write error\n");
	}
} /* end GSM_GPRS_send_cmd_read_result */

/*----------------- send cmd : "at" to GSM/GPRS MODEM ---------------------*/
/*发送一个最简单的AT 命令，查看GPRS模块是否连接正确，
	嵌入式处理器发送命令 ：at
	如果模块工作正常，收到后返回 ：ok */

void GSM_simple_test(int fd)
{
	char *send_buf="at\r"; /* 这里的字符’\r‘表示AT命令的结束 */
	
	GSM_GPRS_send_cmd_read_result(fd,send_buf,RECEIVE_BUF_WAIT_1S);

} /* end GSM_simple_test*/


/*--------------- send cmd : "at+ccid" to GSM/GPRS MODEM ------------*/
/*查看SIM卡的ID号：
	嵌入式处理器发送命令 ：at+ccid
	如果SIM卡正确安装，模块工作正常,收到后返回SIM卡ID，以OK 结束 */

void GSM_read_sim_card_id(int fd)
{
	char *send_buf="at+ccid\r";

	GSM_GPRS_send_cmd_read_result(fd,send_buf,RECEIVE_BUF_WAIT_1S);

} /*end GSM_read_sim_card_id */

/*----------------- send cmd : "atd<tel_num>;" to GSM/GPRS MODEM ------*/
/*----------------- finish call, send cmd:  "ath" to GSM MODEM --------*/
/*呼叫用户输入的号码
 嵌入式处理器发送命令 ：atd<电话号码>;
 按下回车健，将退出此次呼叫  */

void GSM_call(int fd)
{
	char send_buf[17];
	char *send_cmd_ath = "ath\r";
	int i;

	/*input telephone number*/
	bzero(send_buf,sizeof(send_buf));
	
	send_buf[0]='a';
	send_buf[1]='t';
	send_buf[2]='d';
	send_buf[16] = '\0';

	printf("please input telephone number:");

	i = 3;
	while (1)
	{
		send_buf[i]=getchar();
		if (send_buf[i]=='\n') 
		break;
		i++;
	}

	send_buf[i]=';';
	send_buf[i+1]='\r';
	/* end input telphone number */

	/* send cmd */
	GSM_GPRS_send_cmd_read_result(fd,send_buf,RECEIVE_BUF_WAIT_1S);

		/*quit call 按回车键 */
	printf("press ENTER for quit:");
	getchar();

	/* send cmd */
	GSM_GPRS_send_cmd_read_result(fd,send_cmd_ath,RECEIVE_BUF_WAIT_1S);
	
} /* end GSM_call */


/*---------------- wait for GSM/GPRS call signal -------------------*/
/* 不断检查接收缓冲，查看本地号码是否被呼叫
	当检测到有振铃信号时，在屏幕显示RING
	检测一段时间后自动退出	 */

void GSM_wait_call(int fd)
{
	char rcv_buf[2048];
	char *send_cmd_ath = "ath\r";
	int wait_RING;
	
	wait_RING = 10;
	
	while (wait_RING!=0)
	{	
		bzero(rcv_buf,sizeof(rcv_buf));

		if (read_GSM_GPRS_datas(fd,rcv_buf,RECEIVE_BUF_WAIT_1S))
		{
			printf ("%s\n",rcv_buf);
		}
		else
		{
			printf ("read error\n");
		}
		wait_RING--;
	}
	
	GSM_GPRS_send_cmd_read_result(fd,send_cmd_ath,RECEIVE_BUF_WAIT_1S);

	printf("quit wait_call\n");

} /* end GSM_wait_call */

/*------------ GSM/GPRS send short message --------------------------*/
/* 发送短消息 ：输入电话号码与短消息内容，将短消息发出*/

void GSM_Send_Message(int fd)
{
	char cmd_buf[23];
	char short_message_buf[MAX_LEN_OF_SHORT_MESSAGE];
	int  i;
		/* char rcv_buf;*/

	bzero(cmd_buf,sizeof(cmd_buf));
	bzero(short_message_buf,sizeof(short_message_buf));

	printf ("send short message:\n");

	cmd_buf[0]='a';
	cmd_buf[1]='t';
	cmd_buf[2]='+';
	cmd_buf[3]='c';
	cmd_buf[4]='m';
	cmd_buf[5]='g';
	cmd_buf[6]='s';
	cmd_buf[7]='=';
	cmd_buf[8]='"';

	printf ("please input telephone number:");

	i = 9;
	while (1)
	{
		cmd_buf[i]=getchar();
		if (cmd_buf[i]=='\n') break;
		i++;
	}
	cmd_buf[i]='"';
	cmd_buf[i+1]='\r';
	cmd_buf[i+2]='\0';

	/* send cmd :  at+cmgs="(telephone number)"*/
	GSM_GPRS_send_cmd_read_result(fd,cmd_buf,RECEIVE_BUF_WAIT_1S);
	
	/* input short message */
	printf("please input short message:");

	i = 0;
	while(i < MAX_LEN_OF_SHORT_MESSAGE-2)
	{
		short_message_buf[i] = getchar();
		if (short_message_buf[i]=='\n') 
			break; /*接收到回车符时，认为输入完成*/
		i++;
	}
	short_message_buf[i] = 0x1A;
	short_message_buf[i+1] = '\r';
	short_message_buf[i+2] = '\0';

	/* send short message */
	GSM_GPRS_send_cmd_read_result(fd, short_message_buf,RECEIVE_BUF_WAIT_4S);

	printf("\nend send short message\n");
} /* end GSM_Send_Message */

/*----------------- GSM/GPRS read all short message ----------------*/
/*查收所有短消息*/

void GSM_Read_Message(int fd)
{
	char *send_buf="at+cmgl=\"ALL\"\r";
	/*char rcv_buf[2048];*/

	GSM_GPRS_send_cmd_read_result(fd,send_buf,RECEIVE_BUF_WAIT_3S);

	printf("end read all short message\n");

} /* end GSM_Read_Message */

/*-------------- GSM/GPRS Config short message env -----------------*/
/* 配置短消息模式为文本模式;短消息服务中心号码为+8613800100500*/

void GSM_Conf_Message(int fd)
{
	char *send_buf="at+cmgf=1\r";
	char *send_center_buf="at+csca=\"[phone]\"\r";

	GSM_GPRS_send_cmd_read_result(fd,send_buf,RECEIVE_BUF_WAIT_1S);

	/* set short message center number*/
	GSM_GPRS_send_cmd_read_result(fd,send_center_buf,RECEIVE_BUF_WAIT_1S);

	printf("end config short message env\n");
} /* end GSM_Conf_Message */


/*------------------ GSM/GPRS short message --------------------*/
void GSM_short_mesg(int fd)
{
	int flag_sm_run, flag_sm_select;

	flag_sm_run = FUNC_RUN;
	
	while (flag_sm_run == FUNC_RUN)
	{	/*打印短消息功能列表*/
		printf ("\n Select:\n");
		printf ("1 : Send short message \n");
		printf ("2 : Read all short message \n");
		printf ("3 : Config short message env\n");
		printf ("4 : quit\n");
		printf (">");
		scanf("%d",&flag_sm_select);
		getchar();
	
		switch (flag_sm_select)
		{
			case SEND_SHORT_MESSAGE					:
			{ 
				GSM_Send_Message(fd);
				break; 
			}
			case READ_SHORT_MESSAGE					:
			{ 
				GSM_Read_Message(fd);
				break; 
			}
			case CONFIG_SHORT_MESSAGE_ENV		:
			{ 
				GSM_Conf_Message(fd);
				break; 
			}
			case QUIT_SHORT_MESSAGE					:
			{ 
				flag_sm_run = FUNC_NOT_RUN;	
				break; 
			}
			default : 
			{
				printf("please input your select use 1 to 3\n");
			}
		}
	}
	printf ("\n");
} /* end GSM_send_mesg*/

/*--------------------- print -----------------------*/
void print_prompt(void)
{/*显示选择菜单信息*/
	printf ("Select what you want to do:\n");
	printf ("1 : Simple Test\n");
	printf ("2 : Read SIM CARD ID\n");
	printf ("3 : Make A Call\n");
	printf ("4 : Wait A Call\n");
	printf ("5 : Short message\n");
	printf ("6 : Quit\n");
	printf (">");
} /*end print_prompt*/ 

/*---------------- Control GSM/GPRS MODULE ------------------*/
void func_GSM(int fd)
{/*测试函数入口*/
	int flag_func_run;
	int flag_select_func; /*记录用户的选选择输入*/
	
	flag_func_run = FUNC_RUN;/*FUNC_RUN 已经定义为 0 */

	while (flag_func_run == FUNC_RUN)
	{
		print_prompt();			/*显示选择菜单信息*/
		scanf("%d",&flag_select_func);	/*获取用户输入的选择*/
		getchar();/*截取回车符*/

		switch(flag_select_func)
		{/*根据用户的选择调用响应的函数*/
			case SIMPLE_TEST: 
			{
				GSM_simple_test(fd);
				break;
			}
			case READ_SIM_CARD_ID: 
			{
				GSM_read_sim_card_id(fd);
				break;
			}
			case MAKE_A_CALL: 
			{
				GSM_call(fd);
				break;
			}
			case WAIT_A_CALL: 
			{
				GSM_wait_call(fd);
				break;
			}
			case SHORT_MESSAGE:
			{
				GSM_short_mesg(fd);
				break;
			}
			case FUNC_QUIT:
			{ 
				flag_func_run = FUNC_NOT_RUN; /*FUNC_NOT_RUN已定义为1*/
				printf("Quit GSM/GPRS function.  byebye\n");
				break;
				
			}
			default :
			{
				printf("please input your select use 1 to 7\n");
			}
		}
	}
}/*end func_GPRS*/ 

/*---------------------- init seriel port  -----------------------------*/
void init_ttyS(int fd)
{/*配置串口设备*/
	struct termios options;/*定义options，主要串口设置*/
	
	bzero( &options, sizeof( options ));  /*将options的信息清零*/

	cfsetispeed(&options,B9600);     /*设置通讯波特率*/ 
	cfsetospeed(&options,B9600);

	options.c_cflag |= (CRTSCTS | CS8 | CLOCAL | CREAD);
	/*CRTSCTS有流控制   CS8 8位数据位 1位停止位
	CLOCAL 本地连接，无调制调解器控制 CREAD 允许接收数据*/
	
	options.c_iflag = IGNPAR; /*忽略奇偶校验*/
	
	/*设置等待时间和最小接收字符*/
	options.c_cc[VTIME] = 0;
	options.c_cc[VMIN] = 0;

	tcflush(fd, TCIFLUSH);/*TCIFLUSH 刷清输入队列，溢出数据可以接收，但不读*/

	tcsetattr(fd, TCSANOW, &options);/*启用新的串口设置，将其属性赋予串口,TSANOW表示立即生效*/
}/*end init_ttyS*/


/*---------------------- main -----------------------------*/

int main(void)
{
	int fd; /*用于记录文件描述符（端口）*/

	printf("\nGSM/GPRS TESTS\n\n");

	/*以读写方式打开串口  */
	fd = open(DEVICE_TTYS, O_RDWR); 
	/*#define DEVICE_TTYS "/dev/ttyS0"前面已经定义*/

	if (fd == -1)
	{/*串口打开失败*/
		printf("open device %s error\n",DEVICE_TTYS);
	}
	else
	{/*串口成功打开*/
	
		init_ttyS(fd);	/*初始化串口设备*/
		func_GSM(fd);	/*进行GSM/GPRS测试*/
			
		/*关闭串口*/
		if (close(fd)!=0) /*关闭串口*/
		printf("close device %s error",DEVICE_TTYS);
	}
	return 0;
}/*end main*/