Realization of Read-write serial port (i.)

windows open serial port, read and write serial port, automatic identification serial port

This serial port reads and writes asynchronously, namely the non-blocking mode reads and writes the serial port

Serial name such as: "COM3", "COM4", "COM22" and so on

Where COM1 to COM9 can be successfully opened, but COM10 and above open are failed, need special treatment

And COM10 above the open Way is: "\\\\.\\COM10", "\\\\.\\com11", "\\\\.\\COM22" and so on, which is COM10 that the above serial name open mode

Open the serial port:

Open the UART
bool Openuartport (char *uartportname)
{
	bool bresult = true;
	Hcomm = CreateFile (
					  uartportname, 
					  generic_write | Generic_read,	//Access
					  0,							//Do not share
					  NULL,							//The handle returned does not allow the quilt process
					  to inherit open_existing,
					  file_flag_ OVERLAPPED,							//0: Synchronous mode, file_flag_overlapped: Asynchronous mode
					  0								//Do not use temporary file handle
					  );
	if (Invalid_handle_value = = Hcomm)
	{
		printlogcom ("Open Failed!!! \ n ");
		Bresult = false;
	}
	else
	{
		printlogcom ("Open successfully!!! \ n ");
		if (Inituartport (Hcomm, 9600, 8, noparity, onestopbit))
		{
			printlogcom ("Init Uart Port OK!!! \ n ");
		}
		else
		{
			//printlogcom ("Init Uart Port Failed!!! \ n ");
			Bresult = false;
			Close_uartport ();
		}
	}

	return bresult;
}

Initialize the serial port:

Init UART BOOL inituartport (HANDLE hcomm, DWORD baudrate, byte bytesize, byte Parity, byte stopbits) {BOOL bresult = t
	Rue

	Char buffer[50]= "";
	Sets the size of the receive buffer and output buffer DWORD dwinqueue = 1024;
	DWORD dwoutqueue = 1024; if (! Setupcomm (Hcomm, Dwinqueue, Dwoutqueue)) {//printlogcom ("Set in and out Buffer Failed!!!
		\ n ");
	Bresult = false; } else {//printlogcom ("Set Input and Output Buffer OK!!!

		\ n ");
		Set the read-write timeout time to calculate commtimeouts timeouts in milliseconds; For read readtotaltimeouts = ReadTotalTimeoutMultiplier * toreadbytenumber + readtotaltimeoutconstant, timeouts.					ReadIntervalTimeout = Maxdword; Receives a maximum time-out between two characters timeouts.			ReadTotalTimeoutMultiplier = 0; The coefficient timeouts to multiply by reading the number of bytes to read.				ReadTotalTimeoutConstant = 0; Read total time-out constant//for write writetotaltimeouts = writetotaltimeoutmultiplier * Towritebytenumber + Writetotaltimeoutconstan T//timeouts.
		WriteTotalTimeoutMultiplier = 0; Timeouts.

		writetotaltimeoutconstant = 0; if (!
			SetCommTimeouts (Hcomm, &timeouts)) {Printlogcom ("Set read/write timeouts Failed!!!
			\ n ");
		Bresult = false; } else {//printlogcom ("Set read/write timeouts OK!!!
			\ n ");
			Set DCB (device-control-block) DCB DCB; if (! Getcommstate (Hcomm, &DCB)) {//printlogcom ("Get Com DCB Failed!!!
				\ n ");
			Bresult = false; } else {//printlogcom ("Get Com DCB successfully!!!
\ n "); /* sprintf (buffer, "baudrate =%ld", DCB.
				baudrate);
				printlogcom (buffer); sprintf (buffer, "bytesize =%u\n", DCB.
				ByteSize);
				printlogcom (buffer); sprintf (buffer, "Parity =%u\n", DCB.
				Parity);
				printlogcom (buffer); sprintf (buffer, "stopbits =%u\n", DCB.
				StopBits);
				printlogcom (buffer); sprintf (buffer, "XonChar =%d\n", DCB.
				XonChar);
printlogcom (buffer);
				*/memset (&DCB, 0, sizeof (DCB)); Dcb.
				BaudRate = baudrate; Dcb.
				ByteSize = ByteSize; Dcb.
				Parity = Parity; Dcb.
				StopBits = StopBits; Dcb.
	
				XonChar = 1; if (! SetCommState (Hcomm, &DCB)) {//printlogcom ("Set CoM Failed!!!
					\ n ");
				Bresult = false; } else {//printlogcom ("Set Com successfully!!!

					\ n "); Empty the buffer if (!) of the receive cache and output cache. PurgeComm (Hcomm, Purge_rxclear | Purge_txclear)) {//printlogcom ("Clean up in buffer and out buffer Failed!!!
						\ n ");
					Bresult = false; } else {//printlogcom ("Clean on buffer and out buffer OK!!!
					\ n ");
}}}}} return bresult;
 }

Read serial

BOOL Rcvdatafromuartport (HANDLE hcomm, void *rcvbuf, DWORD Torcvdatalen, DWORD *rcveddatalen, lpoverlapped lpoverlapped)
{
	BOOL bresult = true;
	DWORD dwtemprcveddatalen = 0;
	DWORD dwerror;

	if (Clearcommerror (hcomm,&dwerror,null))
	{
		PurgeComm (Hcomm,purge_txabort | purge_txclear);
	}

	if (hcomm! = Invalid_handle_value)
	{
		if (! ReadFile (Hcomm, Rcvbuf, Torcvdatalen, &dwtemprcveddatalen, lpoverlapped))
		{
			if (getlasterror () = = ERROR _io_pending)
			{while
				(! GetOverlappedResult (Hcomm,lpoverlapped,&dwtemprcveddatalen,false))
				{
					if (getlasterror () = = ERROR_IO _incomplete)
					{
						continue;
					}
					else
					{
						clearcommerror (hcomm,&dwerror,null);
						Bresult = false;
						Break
	;
	}}}} else
	{
		bresult = false;
	}
	*rcveddatalen = Dwtemprcveddatalen;
	return bresult;
}

Write serial

BOOL Senddatatouartport (HANDLE hcomm, void *sndbuf, DWORD Senddatalen, DWORD *sentdatalen, lpoverlapped lpoverlapped) 
  {
	BOOL bresult = true;
	DWORD Dwtempsnddatalen;
	DWORD dwerror;

	if (Clearcommerror (hcomm,&dwerror,null))
	{
		PurgeComm (Hcomm,purge_txabort | purge_txclear);
	}

	if (hcomm! = Invalid_handle_value)
	{
		if (! WriteFile (Hcomm, Sndbuf, Senddatalen, &dwtempsnddatalen, lpoverlapped))
		{
			if (getlasterror () = = ERROR_ io_pending)
			{while
				(! GetOverlappedResult (Hcomm,lpoverlapped,&dwtempsnddatalen,false))
				{
					if (getlasterror () = = ERROR_IO_ Incomplete)
					{
						continue;
					}
					else
					{
						clearcommerror (hcomm,&dwerror,null);
						Bresult = false;
						Break
	;
	}}}} else
	{
		bresult = false;
	}
	*sentdatalen = Dwtempsnddatalen;

	return bresult;
}