同學在用FPGA做讀卡器，上位機準備用labview做，因爲不熟悉所以讓我用C#做個備份，備不時之需。
菜鳥級別就跑去給人家幫忙，越幫越忙。他的要求是自定義串口屬性，上位機發送命令，然後讀取每次8096bytes的回覆數據，然後利用接收到的數據畫圖，做一些統計和計算。自己做的過程中將問題分解了下：
1、串口讀取數據
2、讀取的串口數據存儲到txt中
3、在winform中畫圖
從實習開始就有接觸到串口，控制GSM模塊的時候有用過，自以爲比較有點認識。首先是發現原來串口的可選擇的波特率是與電腦的配置有關的。我的直接使用主機自帶的串口最大支持的波特率爲115200；然後通過USB轉串口可以支持最高的256000。接着直接將ReceivedBytesThreshold設置成了8096，準備坐等其成。貌似需要加大ReadBufferSize。
直到sleep 2秒才能保證正確的數據接收，而且還會出現完成數據接收後還會觸發接收事件的現象，接收到的明顯是0，搞不清楚。去查各種C#書，想要看明白串口操作，結果發現C#貌似對網絡支持的很強大的樣子，串口幾乎沒有提及，發帖，qq羣 有的也就是之言片語。有說是開個線程專門去接收的，但是接收事件不是本身就是一個單獨的線程嗎。最後通過一直讀知道收到足夠的數據的方式加快了點速度。 但是同學的labview做出來的沒有什麼明顯的需要接收時間的問題，看來串口操作還是沒設置好啊
當還在讀數據的時候關閉串口，會報錯，添加了個標誌。
將接收數據存儲下來，網上抄襲各種代碼，結果總是得到亂碼。不解啊，看了下之前的一個人家的代碼，原來少了碼制轉換。總算可以存儲了。
畫圖，折騰了好久才知道是用graphics來做的，panel上面做圖片問題老是會有閃爍的很厲害的問題。picturebox的繪製不是說畫上去馬上就表現出來的。
順便貼上自己粗略的代碼，記憶一下。
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.IO.Ports;
using System.Threading;
namespace UpperConputer
{
public partial class Form1 : Form
{
private SerialPort m_serialport = new SerialPort();
//private string fullData = "";
private byte[] fulldata = new byte[8005];
private List<byte> buffer = new List<byte>(8005);
private uint[] intData = new uint[2001];
private bool serialPortMark=false;
private string xmark;
public Graphics graphicsObject;
private Thread threadshow;
private bool portclosing = false;
private bool localPortListening = false;
private delegate void showdelegate();
private DateTime begin, end;
//private string selectedFrequency;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
comboBoxSerialPortN.SelectedIndex = 3;
comboBoxStopBit.SelectedIndex = 0;
comboBoxDataBit.SelectedIndex = 3;
comboBoxBuadRate.SelectedIndex = 6;
comboBoxSelF.SelectedIndex = 7;
//設置雙緩衝
this.SetStyle(ControlStyles.UserPaint, true);
this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);
this.SetStyle(ControlStyles.OptimizedDoubleBuffer, true);
//newthread=new Thread(new ThreadStart(rec));
//newthread.Start();
CreateImage();
}
private void showtext(string str)
{
textBox1.Text = str;
}
private void initializeSerialPort()
{
m_serialport.PortName = comboBoxSerialPortN.Text;
m_serialport.BaudRate =Convert.ToInt32( comboBoxBuadRate.Text);
m_serialport.DataBits = Convert.ToInt16(comboBoxDataBit.Text);
m_serialport.Parity = Parity.None;
//m_serialport.ReadTimeout = 1000;
switch (comboBoxStopBit.Text)
{
case"1":
m_serialport.StopBits = StopBits.One;
break;
case"1.5":
m_serialport.StopBits = StopBits.OnePointFive;
break;
case"2":
m_serialport.StopBits = StopBits.Two;
break;
}
//can used
m_serialport.ReadBufferSize = 10000;
m_serialport.ReceivedBytesThreshold = 1;
//thread_com_read();
}
private void m_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
if (portclosing) return;
try
{
localPortListening = true;
byte firstByte = Convert.ToByte(m_serialport.ReadByte());
int bytesRead = m_serialport.BytesToRead;
byte[] bytesData = new byte[bytesRead + 1];
bytesData[0] = firstByte;
int count = buffer.Count();
for (int i = 1; i <= bytesRead; i++)
{
bytesData[i] = Convert.ToByte(m_serialport.ReadByte());
}
//MessageBox.Show(Convert.ToString(bytesRead));
for (int j = 0; j <=bytesRead; j++)
{
buffer.Add(bytesData[j]);
}
count = buffer.Count();
if (buffer.Count() == 8004)
{
for (int i = 0; i < 8004; i++)
{
fulldata[i] = buffer[i];
}
for (int i = 0, j = 0; i < 8004; i += 4, ++j)
{
intData[j] = System.BitConverter.ToUInt32(fulldata, i);
}
//Thread.Sleep(100);
drawImage(intData);
//Thread.Sleep(100);
buffer.Clear();
}
string str = byteToHexStr(bytesData);
File.WriteAllText("data1.txt", str);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message+" At datareceived");
//處理超時錯誤
}
finally
{
localPortListening = false;
}
//can used
//if (portclosing) return;
//try
//{
// localPortListening = true;
// System.Threading.Thread.Sleep(2000);
// byte[] receivedData = new byte[m_serialport.BytesToRead];
// int count = m_serialport.Read(receivedData, 0, m_serialport.BytesToRead);
// //m_serialport.DiscardInBuffer();//清空接收緩衝區數據
// if (count == 8004)
// {
// for (int i = 0, j = 0; i < 8004; i += 4, ++j)
// {
// intData[j] = System.BitConverter.ToUInt32(receivedData, i);
// }
// }
// else
// {
// return;
// }
// for (int i = 0, j = 0; i < 8004; i += 4, ++j)
// {
// intData[j] = System.BitConverter.ToUInt32(receivedData, i);
// }
// drawImage(intData);
//}
//catch (Exception ex)
//{
// MessageBox.Show(ex.Message);
//}
//finally
//{
// localPortListening = false;
//}
}
public string byteToHexStr(byte[] bytes)
{
string returnStr = "";
if (bytes != null)
{
for (int i = 0; i < bytes.Length; i++)
{
returnStr += bytes[i].ToString("X2");
}
}
return returnStr;
}
private void drawImage(uint[] intData)
{
float xcoordone,xcoordtwo;
double xmax,ymax;
double y1, y2;
int count = 0;
double centreFrequency;
Graphics g = Graphics.FromImage(pictureBox1.Image);
//pictureBox1.Refresh();
//Graphics g = pictureBox1.CreateGraphics();
if (xmark == "0")
{
xcoordone = 40;
g.DrawString("0",new Font("Arial",16),Brushes.Red,new Point(30,378));
}
else
{
xcoordone = 100;
g.DrawString(xmark, new Font("Arial", 16), Brushes.Red, new PointF(90, 378));
}
xmax = xcoordone;
ymax = 0;
xcoordtwo = xcoordone + (float)0.3;
Pen mypen = new Pen(Brushes.Blue, 1);
Pen dashLinePen = new Pen(Brushes.Red, 1);
dashLinePen.DashStyle = System.Drawing.Drawing2D.DashStyle.Dash;
//draw every point and using line to link each other
for (int i = 0; i < intData.Count()-1; ++i)
{
y1 = (double)intData[i] / 16777216 * 300;
y2=(double)intData[i+1]/16777216*300;
// obtain the max point
if (ymax < y1)
{
ymax = y1;
xmax = xcoordone;
count=i;
}
g.DrawLine(new Pen(Color.Black,1),new PointF(xcoordone,(float)(378 - y1)),new PointF(xcoordtwo, (float)(378 - y2)));
xcoordone += (float)0.3;
xcoordtwo += (float)0.3;
}
//畫x軸第二個標示點
int nextxcoord = int.Parse(xmark);
nextxcoord=nextxcoord+2;
g.DrawString(Convert.ToString( nextxcoord),new System.Drawing.Font("Arial",16),Brushes.Red,new PointF(xcoordone,378));
//畫最高頻率線並加註釋
nextxcoord -= 2;
g.DrawLine(dashLinePen, (float)xmax, (float)(378-ymax), (float)xmax, 378);
centreFrequency=nextxcoord+count*0.001;
g.DrawString("f:" + Convert.ToString(centreFrequency),new Font("Arial",16), Brushes.Red, (float)xmax, 388);
//尋找0.707兩點，畫線，計算Q值
mypen.Dispose();
dashLinePen.Dispose();
g.Dispose();
showdelegate show = new showdelegate(showpicture);
this.Invoke(show);
}
private void showpicture()
{
pictureBox1.Visible = false;
pictureBox1.Visible = true;
}
private void CreateImage()
{
pictureBox1.Refresh();
int height = 418, width = 820;
Image image = new Bitmap(820, 418);//定義圖象大小
Graphics g = Graphics.FromImage(image); //定義gdi繪圖對象
Pen mypen = new Pen(Brushes.DeepSkyBlue, 1);
try
{
g.Clear(Color.White);//清除整個繪圖面並以指定背景色填充。
//g.FillRectangle(Brushes.WhiteSmoke, 0, 0, width, height);//填充由一對座標、一個寬度和一個高度指定的矩形的內部。
//畫邊框
g.DrawRectangle(mypen, 0, 0, width - 9, height - 3);//繪製由座標對、寬度和高度指定的矩形。
g.DrawLine(new Pen(Brushes.Black, 1), 40, height - 40, width - 40, height - 40);//x軸
g.DrawLine(new Pen(Brushes.Black, 1), width - 50, height - 30, width - 40, height - 40);//箭頭
g.DrawLine(new Pen(Brushes.Black, 1), width - 50, height - 50, width - 40, height - 40);
g.DrawLine(new Pen(Brushes.Black, 1), 40, height - 40, 40, 40);//y軸
g.DrawLine(new Pen(Brushes.Black, 1), 30, 50, 40, 40);
g.DrawLine(new Pen(Brushes.Black, 1), 50, 50, 40, 40);
g.DrawString("頻率、Q值測試圖", new Font("宋體", 16), Brushes.Green, new PointF(300, 20));
g.DrawString("電壓值", new Font("Arial", 16), Brushes.Aqua, new PointF(50, 40));
g.DrawString("頻率", new Font("宋體", 16), Brushes.Aqua, new PointF(width - 90, height - 30));
g.DrawString("中心頻率：", new Font("宋體", 16), Brushes.Aqua, new PointF(width - 190, 30));
g.DrawString("Q值：", new Font("宋體", 16), Brushes.Aqua, new PointF(width - 140, 50));
mypen.Dispose();
g.Dispose();
pictureBox1.Image = image;
}
catch
{ }
}
private void button1_Click(object sender, EventArgs e)
{
if (!m_serialport.IsOpen)
{
MessageBox.Show("打開串口！");
return;
}
if (comboBoxSelF.Text == "")
{
MessageBox.Show("請選擇測試頻率！");
}
else
{
xmark = comboBoxSelF.Text;
m_serialport.Write(comboBoxSelF.Text);
}
}
private void button2_Click(object sender, EventArgs e)
{
}
private void buttonOpen_Click(object sender, EventArgs e)
{
try
{
if (!m_serialport.IsOpen)
{
//CreateImage();
initializeSerialPort();
m_serialport.Close();
m_serialport.Open();
//thread_com_read();
m_serialport.DataReceived += new SerialDataReceivedEventHandler(m_DataReceived);
serialPortMark = true;
buttonOpen.Text = "關閉串口";
}
else
{
portclosing = true;
while (localPortListening) Application.DoEvents();
serialPortMark = false;
buttonOpen.Text = "打開串口";
m_serialport.DataReceived -= new SerialDataReceivedEventHandler(m_DataReceived);
m_serialport.Close();
portclosing = false;
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
private void buttonRefresh_Click(object sender, EventArgs e)
{
CreateImage();
}
}
}
