rs232.c

win2000下的与下位机UART的串口通信程序

#define _X86_

#include <windef.h>
#include <stdarg.h>
#include <winbase.h>
#include <malloc.h>
#include <winnt.h>

#define RX_BUF_SIZE 1024
#define TX_BUF_SIZE 1024

DCB	dcb;
HANDLE hCom1;
int open_com(void)
{
	int	dwSize;
	LPCOMMPROP lpCom1Prop = (LPCOMMPROP)malloc(sizeof(COMMPROP));
	hCom1 = CreateFile("COM1",GENERIC_READ|GENERIC_WRITE,0,NULL,OPEN_EXISTING,FILE_FLAG_OVERLAPPED,NULL);
	SetupComm(hCom1,RX_BUF_SIZE,TX_BUF_SIZE);

	lpCom1Prop->wPacketLength = sizeof(COMMPROP);
	GetCommProperties(hCom1,lpCom1Prop);
	dwSize = lpCom1Prop->wPacketLength;
	free(lpCom1Prop);
	lpCom1Prop = (LPCOMMPROP)malloc(dwSize);
	GetCommProperties(hCom1,lpCom1Prop);

	if(GetCommState(hCom1,&dcb) == 0)
		return -1;
/*
typedef struct _DCB { // dcb 
DWORD DCBlength;           // sizeof(DCB) 
DWORD BaudRate;            // current baud rate 
DWORD fBinary: 1;          // binary mode, no EOF check 
DWORD fParity: 1;          // enable parity checking 
DWORD fOutxCtsFlow:1;      // CTS output flow control 
DWORD fOutxDsrFlow:1;      // DSR output flow control 
DWORD fDtrControl:2;       // DTR flow control type 
DWORD fDsrSensitivity:1;   // DSR sensitivity 
DWORD fTXContinueOnXoff:1; // XOFF continues Tx 
DWORD fOutX: 1;            // XON/XOFF out flow control 
DWORD fInX: 1;             // XON/XOFF in flow control 
DWORD fErrorChar: 1;       // enable error replacement 
DWORD fNull: 1;            // enable null stripping 
DWORD fRtsControl:2;       // RTS flow control 
DWORD fAbortOnError:1;     // abort reads/writes on error 
DWORD fDummy2:17;          // reserved 
WORD wReserved;            // not currently used 
WORD XonLim;               // transmit XON threshold 
WORD XoffLim;              // transmit XOFF threshold 
BYTE ByteSize;             // number of bits/byte, 4-8 
BYTE Parity;               // 0-4=no,odd,even,mark,space 
BYTE StopBits;             // 0,1,2 = 1, 1.5, 2 
char XonChar;              // Tx and Rx XON character 
char XoffChar;             // Tx and Rx XOFF character 
char ErrorChar;            // error replacement character 
char EofChar;              // end of input character 
char EvtChar;              // received event character 
WORD wReserved1;           // reserved; do not use 
} DCB; 
*/
	dcb.BaudRate = CBR_9600;
	dcb.ByteSize = 8;
	dcb.Parity = NOPARITY;
	dcb.StopBits = ONESTOPBIT;
	SetCommState(hCom1,&dcb);
	dcb.fDtrControl = DTR_CONTROL_ENABLE;
	dcb.fRtsControl = RTS_CONTROL_ENABLE;

	return 0;
}
OVERLAPPED OverLapped;
void wait(int time)
{
	Sleep(time);
}
int send_one_byte(char byte)
{
	int nBytesWrite;
//	int i;
	Sleep(1);
	WriteFile(hCom1,&byte,1,&nBytesWrite,&OverLapped);
	return 0;
}

int send_bytes(char* pIn, int size)
{
	int nBytesWrite;
//	Sleep(1);
	WriteFile(hCom1,pIn,size,&nBytesWrite,&OverLapped);
	return 0;
}

int receive_one_byte(char* byte)
{
	int nBytesRead;

	Sleep(10);
	ReadFile(hCom1,byte,1,&nBytesRead,&OverLapped);
	if(nBytesRead == 1)
		return 0;
	else
		return -1;
	
}

//free(lpCom1Prop);

void set_baud_rate(int baud)
{
	dcb.BaudRate = baud;
	dcb.ByteSize = 8;
	dcb.Parity = NOPARITY;
	dcb.StopBits = ONESTOPBIT;
	SetCommState(hCom1,&dcb);
}

void close_com(void)
{
	CloseHandle(hCom1);
}