基于單片機串口通信的上位機和下位機實踐串口是計算機上一種非常通用設備通信的協(xié)議（不要與通用串行總線Universal Serial Bus或者USB混淆）。大多數(shù)計算機包含兩個基于RS232的串口。串口同時也是儀器儀表設備通用的通信協(xié)議；很多GPIB兼容的設備也帶有RS-232口。同時，串口通信協(xié)議也可以用于獲取遠程采集設備的數(shù)據(jù)。 串口通信的概念非常簡單，串口按位（bit）發(fā)送和接收字節(jié)。盡管比按字節(jié)（byte）的并行通信慢，但是串口可以在使用一根線發(fā)送數(shù)據(jù)的同時用另一根線接收數(shù)據(jù)。它很簡單并且能夠實現(xiàn)遠距離通信。比如IEEE488定義并行通行狀態(tài)時，規(guī)定設備線總常不得超過20米，并且任意兩個設備間的長度不得超過2米；而對于串口而言，長度可達1200米。首先亮出C#的源程序吧。主要界面：只是作為簡單的運用，可以擴展的。源代碼：using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Text;using System.Windows.Forms;using System.IO.Ports;using System.Timers;namespace 單片機功能控制 public partial class Form1 : Form public Form1() InitializeComponent(); SerialPort sp = new SerialPort(); private void button1_Click(object sender, EventArgs e) String str1 = comboBox1.Text;/串口號 String str2 = comboBox2.Text;/波特率 String str3 = comboBox3.Text;/校驗位 String str4 = comboBox5.Text;/停止位 String str5 = comboBox4.Text;/數(shù)據(jù)位 Int32 int2 = Convert.ToInt32(str2);/將字符串轉為整型 Int32 int5 = Convert.ToInt32(str5);/將字符串轉為整型 groupBox3.Enabled = true;/LED控制界面變可選 try if (button1.Text = 打開串口) if (str1 = null) MessageBox.Show(請先選擇串口！, Error); return; sp.Close(); sp = new SerialPort(); sp.PortName = comboBox1.Text;/串口編號 sp.BaudRate = int2;/波特率 switch (str4)/停止位 case 1: sp.StopBits = StopBits.One; break; case 1.5: sp.StopBits = StopBits.OnePointFive; break; case 2: sp.StopBits = StopBits.Two; break; default: MessageBox.Show(Error：參數(shù)不正確, Error); break; switch (str3) case NONE: sp.Parity = Parity.None; break; case ODD: sp.Parity = Parity.Odd; break; case EVEN: sp.Parity = Parity.Even; break; default: MessageBox.Show(Error：參數(shù)不正確, Error); break; sp.DataBits = int5;/數(shù)據(jù)位 sp.Parity = Parity.Even;/設置串口屬性 sp.Open();/打開串口 button1.Text = 關閉串口; textBox1.Text = Convert.ToString(sp.PortName) + 已開啟！; else sp.Close(); button1.Text = 打開串口; groupBox3.Enabled = false;/LED控制界面變灰色 textBox1.Text = Convert.ToString(sp.PortName) + 已關閉！; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void Form1_Load(object sender, EventArgs e) /初始化 textBox1.Text = 歡迎使用簡易的串口助手！; groupBox3.Enabled = false;/LED控制界面變灰色 groupBox6.Enabled = false; groupBox7.Enabled = false; groupBox8.Enabled = false; button3.Enabled = false; button6.Enabled = false; timer1.Start(); try foreach (string com in System.IO.Ports.SerialPort.GetPortNames() /自動獲取串行口名稱 boBox1.Items.Add(com); /默認設置 comboBox1.SelectedIndex = 0;/選擇第一個com口 comboBox2.SelectedIndex = 4;/波特率4800 comboBox3.SelectedIndex = 0;/校驗位NONE comboBox4.SelectedIndex = 0;/停止位為1 comboBox5.SelectedIndex = 0;/數(shù)據(jù)位為8 catch MessageBox.Show(找不到通訊端口！, 串口調試助手); private void timer1_Tick(object sender, EventArgs e) label6.Text = DateTime.Now.ToString(); private void button2_Click(object sender, EventArgs e) try if (button2.Text = 開啟) groupBox6.Enabled = true; radioButton1.Checked = false; radioButton2.Checked = false; radioButton3.Checked = false; radioButton4.Checked = false; checkBox1.Checked = false; checkBox2.Checked = false; checkBox3.Checked = false; checkBox4.Checked = false; checkBox5.Checked = false; checkBox6.Checked = false; checkBox7.Checked = false; checkBox8.Checked = false; button3.Enabled = true; textBox2.Text = String.Empty; button2.Text = 關閉; else groupBox6.Enabled = false; button3.Enabled = false; button2.Text = 開啟; textBox2.Text = String.Empty; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void button3_Click(object sender, EventArgs e) groupBox6.Enabled = true; label7.Text = 已發(fā)送; if (textBox2.Text = ) MessageBox.Show(發(fā)送失敗，請選擇發(fā)送的數(shù)據(jù)！); else sp.WriteLine(textBox2.Text);/往串口寫數(shù)據(jù) private void checkBox1_CheckedChanged(object sender, EventArgs e) try if (checkBox1.Checked) checkBox1.Checked = true; checkBox2.Checked = false; checkBox3.Checked = false; checkBox4.Checked = false; checkBox5.Checked = false; checkBox6.Checked = false; checkBox7.Checked = false; checkBox8.Checked = false; label7.Text = 準備發(fā)送; textBox2.Text = 1; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void checkBox2_CheckedChanged(object sender, EventArgs e) try if (checkBox2.Checked) checkBox1.Checked = false; checkBox2.Checked = true; checkBox3.Checked = false; checkBox4.Checked = false; checkBox5.Checked = false; checkBox6.Checked = false; checkBox7.Checked = false; checkBox8.Checked = false; label7.Text = 準備發(fā)送; textBox2.Text = 2; radioButton1.Checked = false; radioButton2.Checked = false; radioButton3.Checked = false; radioButton4.Checked = false; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void checkBox3_CheckedChanged(object sender, EventArgs e) try if (checkBox3.Checked) checkBox1.Checked = false; checkBox2.Checked = false; checkBox3.Checked = true; checkBox4.Checked = false; checkBox5.Checked = false; checkBox6.Checked = false; checkBox7.Checked = false; checkBox8.Checked = false; radioButton1.Checked = false; radioButton2.Checked = false; radioButton3.Checked = false; radioButton4.Checked = false; label7.Text = 準備發(fā)送; textBox2.Text = 3; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void checkBox4_CheckedChanged(object sender, EventArgs e) try if (checkBox4.Checked) checkBox1.Checked = false; checkBox2.Checked = false; checkBox3.Checked = false; checkBox4.Checked = true; checkBox5.Checked = false; checkBox6.Checked = false; checkBox7.Checked = false; checkBox8.Checked = false; radioButton1.Checked = false; radioButton2.Checked = false; radioButton3.Checked = false; radioButton4.Checked = false; label7.Text = 準備發(fā)送; textBox2.Text = 4; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void checkBox5_CheckedChanged(object sender, EventArgs e) try if (checkBox5.Checked) checkBox1.Checked = false; checkBox2.Checked = false; checkBox3.Checked = false; checkBox4.Checked = false; checkBox5.Checked = true; checkBox6.Checked = false; checkBox7.Checked = false; checkBox8.Checked = false; radioButton1.Checked = false; radioButton2.Checked = false; radioButton3.Checked = false; radioButton4.Checked = false; label7.Text = 準備發(fā)送; textBox2.Text = 5; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void checkBox6_CheckedChanged(object sender, EventArgs e) try if (checkBox6.Checked) checkBox1.Checked = false; checkBox2.Checked = false; checkBox3.Checked = false; checkBox4.Checked = false; checkBox5.Checked = false; checkBox6.Checked = true; checkBox7.Checked = false; checkBox8.Checked = false; radioButton1.Checked = false; radioButton2.Checked = false; radioButton3.Checked = false; radioButton4.Checked = false; label7.Text = 準備發(fā)送; textBox2.Text = 6; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void checkBox7_CheckedChanged(object sender, EventArgs e) try if (checkBox7.Checked) checkBox1.Checked = false; checkBox2.Checked = false; checkBox3.Checked = false; checkBox4.Checked = false; checkBox5.Checked = false; checkBox6.Checked = false; checkBox7.Checked = true; checkBox8.Checked = false; radioButton1.Checked = false; radioButton2.Checked = false; radioButton3.Checked = false; radioButton4.Checked = false; label7.Text = 準備發(fā)送; textBox2.Text = 7; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void checkBox8_CheckedChanged(object sender, EventArgs e) try if (checkBox8.Checked) checkBox1.Checked = false; checkBox2.Checked = false; checkBox3.Checked = false; checkBox4.Checked = false; checkBox5.Checked = false; checkBox6.Checked = false; checkBox7.Checked = false; checkBox8.Checked = true; radioButton1.Checked = false; radioButton2.Checked = false; radioButton3.Checked = false; radioButton4.Checked = false; label7.Text = 準備發(fā)送; textBox2.Text = 8; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void button5_Click(object sender, EventArgs e) try if (button5.Text = 開啟) radioButton1.Checked = false; radioButton2.Checked = false; radioButton3.Checked = false; radioButton4.Checked = false; checkBox1.Checked = false; checkBox2.Checked = false; checkBox3.Checked = false; checkBox4.Checked = false; checkBox5.Checked = false; checkBox6.Checked = false; checkBox7.Checked = false; checkBox8.Checked = false; groupBox7.Enabled = true; button6.Enabled = true; textBox2.Text = String.Empty; button5.Text = 關閉; else groupBox7.Enabled = false; button6.Enabled = false; button5.Text = 開啟; textBox2.Text = String.Empty; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void button6_Click(object sender, EventArgs e) label7.Text = 已發(fā)送; if (textBox2.Text = ) MessageBox.Show(發(fā)送失敗。請選擇發(fā)送的數(shù)據(jù)！); else sp.WriteLine(textBox2.Text);/往串口寫數(shù)據(jù) private void radioButton1_CheckedChanged(object sender, EventArgs e) try if (radioButton1.Checked) label7.Text = 準備發(fā)送; textBox2.Text = 9; checkBox1.Checked = false; checkBox2.Checked = false; checkBox3.Checked = false; checkBox4.Checked = false; checkBox5.Checked = false; checkBox6.Checked = false; checkBox7.Checked = false; checkBox8.Checked = false; catch (Exception er) MessageBox.Show(Error: + er.Message, Error); return; private void radioButton2_CheckedChanged(object sender, EventArgs e) try if (radioButton2.Checked) label7.Text = 準備發(fā)送; textBox2.Text = a; checkBox1.Checked = false; checkBox2.Checked = false; checkBox3.Checked = false; checkBox4.Checked = false; checkBox5.Checked = false; checkBox6.Checked = false; che