serial.c

DSP5416芯片的串行通信源代码

/* 5416-A板：
	使用直连的串口通信电缆;
	启动"串口调试助手.exe";
	PC机发送信息以一个"."为结束标志
*/
ioport unsigned int port2000,port2001,port2002,port2003,port2004,port2005,port2006,port2007;

#define RBR	port2000
#define THR	port2000
#define IER	port2001
#define IIR	port2002
#define FCR	port2002
#define LCR	port2003
#define MCR	port2004
#define LSR	port2005
#define MSR	port2006
#define SCR	port2007
#define DLL	port2000
#define DLM	port2001

void wait(int nWait);

char cString[17]={ "Hello PC!,Over|" },cReceive,cBuffer[17],cAnswer[16]={"Oh,you say"};
int bReceive,nLen;

main()
{
	unsigned int uWork;
	int i,k;
	
	bReceive=0;
	LCR = 0x80; 
	DLL = 0x18;    
	DLM = 0x00;  
	LCR = 0x03;    
	FCR = 0x01;
	MCR = 0x20;
	IER = 0x00;      
	
	while ( 1 )
	{
		if ( bReceive==0 )
		{
			for ( i=0;i<16;i++ )
			{
				do
				{ 
					uWork=LSR;
				} while ( uWork&0x040 != 0x040 );
				THR=cString[i];
				wait(1024);		
			}
		}
		else
		{
			for ( i=0;i<10;i++ )
			{
				do
				{ 
					uWork=LSR;
				} while ( uWork&0x040 != 0x040 );
				THR=cAnswer[i];
				wait(1024);		
			}
			do
			{ 
				uWork=LSR;
			} while ( uWork&0x040 != 0x040 );
			THR='\"';
			for ( i=0;i<nLen;i++ )
			{
				do
				{ 
					uWork=LSR;
				} while ( uWork&0x040 != 0x040 );
				THR=cBuffer[i];
				wait(1024);		
			}
			do
			{ 
				uWork=LSR;
			} while ( uWork&0x040 != 0x040 );
			THR='\"';
			wait(1024);		
			for ( i=9;i<16;i++ )
			{
				do
				{ 
					uWork=LSR;
				} while ( uWork&0x040 != 0x040 );
				THR=cString[i];
				wait(1024);		
			}
		}
		k=0; bReceive=0;
		while ( 1 )
		{
			do
			{
				uWork=LSR;
			} while ( (uWork&1)==0 );
			cReceive=RBR;
			cBuffer[k]=cReceive&0x0ff; 
			if ( cReceive=='.' )
			{
				cBuffer[k+1]='\0';
				nLen=k+1;
				bReceive=1;
				break;
			}
			k++; k%=16;
		}
	}
}

void wait(int nWait)
{
	int i,j,k=0;
	for ( i=0;i<nWait;i++ )
		for ( j=0;j<64;j++ )
			k++;
}