rscomm.c

本程序在S3C44B0 uClinux的嵌入式GUI

//RsComm.c 串口通讯

 #define TIME_OUT_CONST_A   1500
 
 typedef unsigned char BYTE;
 typedef unsigned int  WORD;
 typedef unsigned long DWORD;


 //串口发送数据
void COM_SendString( int COM_PortNo,BYTE str[],int len )
 { int i,time;
   
	for(i=0; i<len; i++){
		//time = 100000; //this delay must be reserved, because the IC card reader processing is lower speed
		//while(time --);
		while(!(COM_PortStatus(COM_PortNo)));
		COM_Send(COM_PortNo,str[i]);
	}
 }

 //串口按保利协议接收数据
 //返回:cnt>0->接收到数据个数,-1->累加和出错,-2->超时，
 //ESC,CMD80,SUBxx,TotalLen=8,"abc",cs ->测试通讯协议
 //返回:cnt>0->接收到数据个数,-1->累加和出错,-2->超时，
int  ReceiDataAsPOLYProtocal_0( int PortNo , char buf[] )
 { int cnt=0,step=0,len; long timeout=0; char ChkSum=0;
   BYTE CommonByteC;

   do{
      if( COM_RecvStatus( PortNo ) ) { //串口 接收指针 头 == 尾->无数据在接收缓冲区
          COM_Receive( PortNo , &CommonByteC ); //将数据从接收缓冲区取出->CommonByteC
          
          switch(step){
             case 0: //ESC
                     if(CommonByteC == 0x1B){
                        buf[cnt++] = CommonByteC; step = 1;
                     }
                     break;
             case 1: //CMD80,SUBxx,
                     buf[cnt++] = CommonByteC;
                     if(cnt==3) step = 2;
                     break;
             case 2: //len
                     buf[cnt++] = CommonByteC; len = CommonByteC;
                     if(len==5) step = 4; //无数据内容,直接接收 累加和
                     else       step = 3; //有数据内容
                     break;
             case 3: //data
                     buf[cnt++] = CommonByteC;
                     if((len-1)==cnt) step = 4;
                     break;
             case 4: //cs
                     buf[cnt++] = CommonByteC;
                     ////if(ChkSum != CommonByteC) cnt = -1;
                     step = 5;
                     break;
          } //end switch
          ChkSum += CommonByteC; //累加和
          if(step == 5) //接收 数据结束
             break;
      } //end if( )
      timeout ++;
   } while( timeout < TIME_OUT_CONST_A * 10);
   if( timeout == TIME_OUT_CONST_A * 10)
      cnt = -2; //超时
   return cnt;
 }

 /*
int COM_ReceiveStringAsPoly( int COM_PortNo,BYTE str[] )
 { int i, time;


        //接收
	for(i=0; i<6; i++){
		while(!(COM_RecvStatus(1)));
		COM_Receive(1,reader_r[0]);
		printf("COM_1 data = %2x\n",reader_r[0]);
	}
 }
 */