using System;
using System.Drawing;
using System.Collections;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Text;

namespace PPCReadCommPort
{
	/// <summary>
	/// Summary description for Form1.
	/// </summary>
	public class Form1 : System.Windows.Forms.Form
	{
		private System.Windows.Forms.Button btnOpenFile;
		private System.Windows.Forms.TextBox textBox1;
		private System.Windows.Forms.Button btnCloseFile;
		private System.Windows.Forms.Button btnConfigure;
		private System.Windows.Forms.TextBox textBox2;
		private System.Windows.Forms.Label label1;
		private System.Windows.Forms.Button btnReadFile;
	
		#region VS Stuff
		public Form1()
		{
			//
			// Required for Windows Form Designer support
			//
			InitializeComponent();

			//
			// TODO: Add any constructor code after InitializeComponent call
			//
		}
#if COMPLETE_FRAMEWORK
		/// <summary>
		/// Clean up any resources being used.
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			base.Dispose( disposing );
		}
#endif
		#region Windows Form Designer generated code
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent()
		{
			this.btnOpenFile = new System.Windows.Forms.Button();
			this.btnReadFile = new System.Windows.Forms.Button();
			this.textBox1 = new System.Windows.Forms.TextBox();
			this.btnCloseFile = new System.Windows.Forms.Button();
			this.btnConfigure = new System.Windows.Forms.Button();
			this.textBox2 = new System.Windows.Forms.TextBox();
			this.label1 = new System.Windows.Forms.Label();
			// 
			// btnOpenFile
			// 
			this.btnOpenFile.Location = new System.Drawing.Point(77, 36);
			this.btnOpenFile.Text = "Open Port";
			this.btnOpenFile.Click += new System.EventHandler(this.btnOpenFile_Click);
			// 
			// btnReadFile
			// 
			this.btnReadFile.Location = new System.Drawing.Point(78, 153);
			this.btnReadFile.Text = "Read Data";
			this.btnReadFile.Click += new System.EventHandler(this.btnReadFile_Click);
			// 
			// textBox1
			// 
			this.textBox1.Location = new System.Drawing.Point(86, 10);
			this.textBox1.Size = new System.Drawing.Size(57, 20);
			this.textBox1.Text = "";
			// 
			// btnCloseFile
			// 
			this.btnCloseFile.Location = new System.Drawing.Point(77, 246);
			this.btnCloseFile.Text = "Close Port";
			this.btnCloseFile.Click += new System.EventHandler(this.btnCloseFile_Click);
			// 
			// btnConfigure
			// 
			this.btnConfigure.Location = new System.Drawing.Point(68, 118);
			this.btnConfigure.Size = new System.Drawing.Size(98, 23);
			this.btnConfigure.Text = "Configure Baud";
			this.btnConfigure.Click += new System.EventHandler(this.btnConfigure_Click);
			// 
			// textBox2
			// 
			this.textBox2.Location = new System.Drawing.Point(95, 89);
			this.textBox2.Size = new System.Drawing.Size(38, 20);
			this.textBox2.Text = "";
			// 
			// label1
			// 
			this.label1.Location = new System.Drawing.Point(6, 178);
			this.label1.Size = new System.Drawing.Size(230, 44);
			// 
			// Form1
			// 
			this.ClientSize = new System.Drawing.Size(240, 295);
			this.Controls.Add(this.label1);
			this.Controls.Add(this.textBox2);
			this.Controls.Add(this.btnConfigure);
			this.Controls.Add(this.btnCloseFile);
			this.Controls.Add(this.textBox1);
			this.Controls.Add(this.btnReadFile);
			this.Controls.Add(this.btnOpenFile);
			this.Text = "Form1";
			this.Load += new System.EventHandler(this.Form1_Load);
			this.Closed += new System.EventHandler(this.Form1_Closed);

		}
		#endregion

		/// <summary>
		/// The main entry point for the application.
		/// </summary>

		static void Main() 
		{
			Application.Run(new Form1());
		}

		#endregion

		int		handleSerialPort	= -1;
		bool	bCycle				= false;
		string	port				= "COM4:";
		int		Baudrate			= 4800;

		# region Structures and Classes
		//[StructLayout(LayoutKind.Sequential, Pack=1)] // for desktop uncomment this line
		public class OVERLAPPED
		{
			public int Internal;
			public int InternalHigh;
			public int Offset;
			public int OffsetHigh;
			public int hEvent;
		}

		//[StructLayout(LayoutKind.Sequential, Pack=1)]
		public struct DCB
		{
			public int DCBlength;                     
			public int BaudRate;
			public int fBinary;     ///* Binary Mode (skip EOF check)    
			public int fParity;     // Enable parity checking          
			public int fOutxCtsFlow; // CTS handshaking on output       
			public int fOutxDsrFlow; // DSR handshaking on output       
			public int fDtrControl;  // DTR Flow control                
			public int fDsrSensitivity; // DSR Sensitivity              
			public int fTXContinueOnXoff; //Continue TX when Xoff sent 
			public int fOutX;        //Enable output X-ON/X-OFF        
			public int fInX;         //Enable input X-ON/X-OFF         
			public int fErrorChar;   //Enable Err Replacement          
			public int fNull;        //Enable Null stripping           
			public int fRtsControl;   //Rts Flow control                
			public int fAbortOnError;  //Abort all reads and writes on Error 
			public int fDummy;      //Reserved                        
			public Int16 wReserved;        //Not currently used              
			public Int16 XonLim;           //Transmit X-ON threshold         
			public Int16 XoffLim;          //Transmit X-OFF threshold        
			public byte ByteSize;         //Number of bits/byte, 4-8        
			public byte Parity;           //0-4=None,Odd,Even,Mark,Space    
			public byte StopBits;         //0,1,2 = 1, 1.5, 2               
			public char XonChar;          //Tx and Rx X-ON character        
			public char XoffChar;         //Tx and Rx X-OFF character       
			public char ErrorChar;        //Error replacement char          
			public char EofChar;          //End of Input character          
			public char EvtChar;          //Received Event character        
			public Int16 wReserved1;       //Fill for now. 

		} // end DCB Struct

		#endregion

		#region DllImports
		[DllImport("coredll.dll")] 
		private static extern int SetCommState(int hCommDev, ref DCB lpDCB);

		[DllImport("coredll.dll")] 
		private static extern int GetCommState(int hCommDev, ref DCB lpDCB) ;

		[DllImport("coredll.dll")] 
		static extern int ReadFile(int hFile, Byte[] Buffer, int nNumberOfBytesToRead, ref int lpNumberOfBytesRead, ref OVERLAPPED lpOverlapped ) ;

		[DllImport("coredll.dll")] 
		static extern int CreateFile(string lpFileName, int dwDesiredAccess, int dwShareMode, int lpSecurityAttributes, int dwCreationDisposition, int dwFlagsAndAttributes, int hTemplateFile) ;

		[DllImport("coredll.dll")] 
		static extern int CloseHandle(int hObject) ;
		#endregion

		private void Form1_Load(object sender, System.EventArgs e)
		{
			textBox1.Text = port;
			textBox2.Text = Convert.ToString(Baudrate);
		}

		private void btnOpenFile_Click(object sender, System.EventArgs e)
		{
			port = textBox1.Text;

			// Let's try to close the Port if we have a handle
			CloseComm(ref handleSerialPort, port);
			
			handleSerialPort = CreateFile(port, unchecked((int)0x80000000) | 0x40000000, 0, 0, 3, 0, 0);
			if (handleSerialPort < 1)
			{
				label1.Text = "Error: Unable to open port: " + port + " " + Convert.ToString(handleSerialPort);
				return;
			}

			label1.Text = "opened " + port + Convert.ToString(handleSerialPort);
		} // end btnOpenFile_Click

		private void btnReadFile_Click(object sender, System.EventArgs e)
		{
			int	iRc	= -1;
			bCycle = true;
			int		BytesToRead			= 40;
			int		BytesActuallyRead	= 0;
			byte[]	Buffer;

			if (handleSerialPort != -1)

			{

				// Loop and grab data from COM buffer and display in Label control
				while (bCycle)
				{
					Buffer = new Byte[BytesToRead];

					OVERLAPPED O = new OVERLAPPED();

					iRc = ReadFile(handleSerialPort, Buffer, BytesToRead, ref BytesActuallyRead, ref O);

					if (iRc < 1) label1.Text = "Error: Unable to read from " + port + " " + Convert.ToString(iRc);
					else label1.Text = Encoding.GetEncoding("ASCII").GetString(Buffer,0,BytesToRead);

					Application.DoEvents();
				}
			}
			else label1.Text = "Error: Comm Port not open";

		} // end btnReadFile_Click

		private void btnConfigure_Click(object sender, System.EventArgs e)
		{

			if (handleSerialPort != -1)
			{

				DCB dcb = new DCB();

				// Not needed for NETCF
				//dcb.DCBlength = Marshal.SizeOf(dcb);

				// Get existing Comm State
				GetCommState (handleSerialPort, ref dcb); // Get the default port setting information.

				string oldbaud = dcb.BaudRate.ToString();

				int newbaud = Baudrate;
				
				try { newbaud = Convert.ToInt32(textBox2.Text); }
				catch{}

				// Change the DCB structure settings.
				dcb.BaudRate = newbaud; // Set to Baud rate defined in textbox
				dcb.fBinary = 1;              // Binary mode; no EOF check 
				dcb.fParity = 1;              // Enable parity checking 
				dcb.fOutxCtsFlow = 0;         // No CTS output flow control 
				dcb.fOutxDsrFlow = 0;         // No DSR output flow control 
				dcb.fDtrControl = 1;          // DTR_CONTROL_ENABLE = 1 // DTR flow control type 
				dcb.fDsrSensitivity = 0;      // DSR sensitivity 
				dcb.fTXContinueOnXoff = 1;    // XOFF continues Tx 
				dcb.fOutX = 0;                // No XON/XOFF out flow control 
				dcb.fInX = 0;                 // No XON/XOFF in flow control 
				dcb.fErrorChar = 0;           // Disable error replacement 
				dcb.fNull = 0;                // Disable null stripping 
				dcb.fRtsControl = 1;		  // RTS_CONTROL_ENABLE = 1 // RTS flow control 
				dcb.fAbortOnError = 0;        // Do not abort reads/writes on error
				dcb.ByteSize = 8;             // Number of bits/byte, 4-8 
				dcb.Parity = 0;               // 0-4=no,odd,even,mark,space 
				dcb.StopBits = 0;             // 0,1,2 = 1, 1.5, 2 

				// Attempt to set new Comm state
				int result = SetCommState(handleSerialPort, ref dcb);

				if (result != 0)
				{
					//dwError = GetLastError(); // Could not configure the serial port.
					label1.Text = "Error Setting State. Result: " + result.ToString();
				}
				else label1.Text = "was: " + oldbaud + " baud, setting to: " + newbaud.ToString() + " baud.";
			}
			else label1.Text = "Error: Comm Port not open";

		} // end btnConfigure_Click

		private void btnCloseFile_Click(object sender, System.EventArgs e)
		{
			// Try to close Comm Port
			CloseComm(ref handleSerialPort, port);
		}

		private void Form1_Closed(object sender, System.EventArgs e)
		{
			// Attempt to close Comm port before exiting.
			CloseComm(ref handleSerialPort, port);
		}

		private void CloseComm(ref int hComm, string strPort)
		{
			// stop reading loop
			bCycle = false;

			if (hComm != -1 )
			{
				int result = CloseHandle(hComm);
				if (result < 1) label1.Text = "Error: Failed to close " + strPort;
				else
				{
					label1.Text = "Closed " + strPort + " Successfully";
					hComm = -1;
				}
			}
		} // end CloseComm

	}// end class

}// end namespace