modbus rtu的实现与modbus tcp的实现类似 c#modbus tcp的学习及master的实现
我们还是需要借用一个开源库nmodbus4,在vs中.打开nuget管理器.安装nmodbus4
具体实现,具体实现与之前的modbus tcp的实现类似 ,只是在实例化master时将tcpclient换为串行端口资源serialport,并在实例化是设置好端口所需参数(端口名,波特率,校验位,停止位,数据位)
1 using system;
2 using system.collections.generic;
3 using system.componentmodel;
4 using system.data;
5 using system.drawing;
6 using system.linq;
7 using system.text;
8 using system.threading.tasks;
9 using system.windows.forms;
10 using modbus.device;
11 using system.net.sockets;
12 using system.threading;
13 using system.io.ports;
14
15 namespace modbusrtu
16 {
17 public partial class form1 : form
18 {
19 private static imodbusmaster master;
20 private static serialport port;
21 //写线圈或写寄存器数组
22 private bool[] coilsbuffer;
23 private ushort[] registerbuffer;
24 //功能码
25 private string functioncode;
26 //参数(分别为站号,起始地址,长度)
27 private byte slaveaddress;
28 private ushort startaddress;
29 private ushort numberofpoints;
30 //串口参数
31 private string portname;
32 private int baudrate;
33 private parity parity;
34 private int databits;
35 private stopbits stopbits;
36
37 public form1()
38 {
39 initializecomponent();
40 }
41 private void form1_load(object sender, eventargs e)
42 {
43 cmb_portname.selectedindex = 0;
44 cmb_baud.selectedindex = 5;
45 cmb_parity.selectedindex = 2;
46 cmb_databbits.selectedindex = 1;
47 cmb_stopbits.selectedindex = 0;
48 }
49 private serialport initserialportparameter()
50 {
51 if (cmb_portname.selectedindex < 0 || cmb_baud.selectedindex < 0 || cmb_parity.selectedindex < 0 || cmb_databbits.selectedindex < 0 || cmb_stopbits.selectedindex < 0)
52 {
53 messagebox.show("请选择串口参数");
54 return null;
55 }
56 else
57 {
58
59 portname = cmb_portname.selecteditem.tostring();
60 baudrate = int.parse(cmb_baud.selecteditem.tostring());
61 switch (cmb_parity.selecteditem.tostring())
62 {
63 case "奇":
64 parity = parity.odd;
65 break;
66 case "偶":
67 parity = parity.even;
68 break;
69 case "无":
70 parity = parity.none;
71 break;
72 default:
73 break;
74 }
75 databits = int.parse(cmb_databbits.selecteditem.tostring());
76 switch (cmb_stopbits.selecteditem.tostring())
77 {
78 case "1":
79 stopbits = stopbits.one;
80 break;
81 case "2":
82 stopbits = stopbits.two;
83 break;
84 default:
85 break;
86 }
87 port = new serialport(portname, baudrate, parity, databits, stopbits);
88 return port;
89 }
90 }
91 /// <summary>
92 /// 读/写
93 /// </summary>
94 /// <param name="sender"></param>
95 /// <param name="e"></param>
96 private void button1_click(object sender, eventargs e)
97 {
98 try
99 {
100 //初始化串口参数
101 initserialportparameter();
102
103 master = modbusserialmaster.creatertu(port);
104
105 executefunction();
106 }
107 catch (exception)
108 {
109 messagebox.show("初始化异常");
110 }
111 }
112
113 private async void executefunction()
114 {
115 try
116 {
117 //每次操作是要开启串口 操作完成后需要关闭串口
118 //目的是为了slave更换连接是不报错
119 if (port.isopen == false)
120 {
121 port.open();
122 }
123 if (functioncode != null)
124 {
125 switch (functioncode)
126 {
127 case "01 read coils"://读取单个线圈
128 setreadparameters();
129 coilsbuffer = master.readcoils(slaveaddress, startaddress, numberofpoints);
130
131 for (int i = 0; i < coilsbuffer.length; i++)
132 {
133 setmsg(coilsbuffer[i] + " ");
134 }
135 setmsg("\r\n");
136 break;
137 case "02 read discrete inputs"://读取输入线圈/离散量线圈
138 setreadparameters();
139
140 coilsbuffer = master.readinputs(slaveaddress, startaddress, numberofpoints);
141 for (int i = 0; i < coilsbuffer.length; i++)
142 {
143 setmsg(coilsbuffer[i] + " ");
144 }
145 setmsg("\r\n");
146 break;
147 case "03 read holding registers"://读取保持寄存器
148 setreadparameters();
149 registerbuffer = master.readholdingregisters(slaveaddress, startaddress, numberofpoints);
150 for (int i = 0; i < registerbuffer.length; i++)
151 {
152 setmsg(registerbuffer[i] + " ");
153 }
154 setmsg("\r\n");
155 break;
156 case "04 read input registers"://读取输入寄存器
157 setreadparameters();
158 registerbuffer = master.readinputregisters(slaveaddress, startaddress, numberofpoints);
159 for (int i = 0; i < registerbuffer.length; i++)
160 {
161 setmsg(registerbuffer[i] + " ");
162 }
163 setmsg("\r\n");
164 break;
165 case "05 write single coil"://写单个线圈
166 setwriteparametes();
167 await master.writesinglecoilasync(slaveaddress, startaddress, coilsbuffer[0]);
168 break;
169 case "06 write single registers"://写单个输入线圈/离散量线圈
170 setwriteparametes();
171 await master.writesingleregisterasync(slaveaddress, startaddress, registerbuffer[0]);
172 break;
173 case "0f write multiple coils"://写一组线圈
174 setwriteparametes();
175 await master.writemultiplecoilsasync(slaveaddress, startaddress, coilsbuffer);
176 break;
177 case "10 write multiple registers"://写一组保持寄存器
178 setwriteparametes();
179 await master.writemultipleregistersasync(slaveaddress, startaddress, registerbuffer);
180 break;
181 default:
182 break;
183 }
184
185 }
186 else
187 {
188 messagebox.show("请选择功能码!");
189 }
190 port.close();
191 }
192 catch (exception ex)
193 {
194
195 messagebox.show(ex.message);
196 }
197 }
198 private void combobox1_selectedindexchanged(object sender, eventargs e)
199 {
200 if (combobox1.selectedindex >= 4)
201 {
202 groupbox2.enabled = true;
203 groupbox1.enabled = false;
204 }
205 else
206 {
207 groupbox1.enabled = true;
208 groupbox2.enabled = false;
209 }
210 combobox1.invoke(new action(() => { functioncode = combobox1.selecteditem.tostring(); }));
211 }
212
213 /// <summary>
214 /// 初始化读参数
215 /// </summary>
216 private void setreadparameters()
217 {
218 if (txt_startaddr1.text == "" || txt_slave1.text == "" || txt_length.text == "")
219 {
220 messagebox.show("请填写读参数!");
221 }
222 else
223 {
224 slaveaddress = byte.parse(txt_slave1.text);
225 startaddress = ushort.parse(txt_startaddr1.text);
226 numberofpoints = ushort.parse(txt_length.text);
227 }
228 }
229 /// <summary>
230 /// 初始化写参数
231 /// </summary>
232 private void setwriteparametes()
233 {
234 if (txt_startaddr2.text == "" || txt_slave2.text == "" || txt_data.text == "")
235 {
236 messagebox.show("请填写写参数!");
237 }
238 else
239 {
240 slaveaddress = byte.parse(txt_slave2.text);
241 startaddress = ushort.parse(txt_startaddr2.text);
242 //判断是否写线圈
243 if (combobox1.selectedindex == 4 || combobox1.selectedindex == 6)
244 {
245 string[] strarr = txt_data.text.split(' ');
246 coilsbuffer = new bool[strarr.length];
247 //转化为bool数组
248 for (int i = 0; i < strarr.length; i++)
249 {
250 // strarr[i] == "0" ? coilsbuffer[i] = true : coilsbuffer[i] = false;
251 if (strarr[i] == "0")
252 {
253 coilsbuffer[i] = false;
254 }
255 else
256 {
257 coilsbuffer[i] = true;
258 }
259 }
260 }
261 else
262 {
263 //转化ushort数组
264 string[] strarr = txt_data.text.split(' ');
265 registerbuffer = new ushort[strarr.length];
266 for (int i = 0; i < strarr.length; i++)
267 {
268 registerbuffer[i] = ushort.parse(strarr[i]);
269 }
270 }
271 }
272 }
273
274 /// <summary>
275 /// 清除文本
276 /// </summary>
277 /// <param name="sender"></param>
278 /// <param name="e"></param>
279 private void button2_click(object sender, eventargs e)
280 {
281 richtextbox1.clear();
282 }
283 /// <summary>
284 /// setmessage
285 /// </summary>
286 /// <param name="msg"></param>
287 public void setmsg(string msg)
288 {
289 richtextbox1.invoke(new action(() => { richtextbox1.appendtext(msg); }));
290 }
291
292 }
293 }
接下来开始测试
在这里 因为要用到串口,而我的笔记本没有串口,所以需要借助一个工具
virtual serial port dirver 虚拟串口工具
链接：https://pan.baidu.com/s/1opgre3gs-hwfoa_dp9qyyg
提取码：2afu
借用这个工具我们添加两个虚拟串口 com1和com2 点击add virtual pair 添加
设置modbus slave,选择连接方式为串口,选择对应端口,模式选择rtu,建立连接
接下来运行我们自己的modbus rtu master
设置串口参数(波特率,数据位,奇偶校验,停止位)要与slave的串口参数一致
我们测试 功能码 0x01 读一组线圈
测试完成,数据正常,其他的功能码经测试数据正常,有兴趣的可以自行测试
到此为止,modbus的学习到此告一段落
以上都为我自行学习并实现,如有错误之处,望大家不吝赐教,感谢(抱拳~)
程序源代码:
链接：https://pan.baidu.com/s/1mpahrixlbsdb7h2epentra
提取码：b5w6
黄山市民网：https://www.huangshanshimin.com/
