IoTClient开发6 - S7-200SmarTcp协议客户端实现

环境和工具

服务端电脑ip：192.168.1.130
客户端电脑ip：192.168.1.120
1、在服务端电脑运行iotclienttool

2、运行wireshark

3、在客户端电脑运行iotclienttool

4、wireshark得到如下报文

报文分析，plc的连接

我们看到上面连接西门子plc抓取到了八条报文。其中有tcp的三次握手、和对最后一次响应的回复，然后就是西门子特有的两次初始化指令的请求和响应。

两次初始化指令

不同型号的西门子plc有不同的初始化指令，同型号的指令固定不变。

代码实现对plc的连接

//直接是wireshark抓取到的报文数据
var command1 = new byte[22]
{
    0x03,0x00,0x00,0x16,0x11,0xe0,0x00,0x00,
    0x00,0x01,0x00,0xc1,0x02,0x10,0x00,0xc2,
    0x02,0x03,0x00,0xc0,0x01,0x0a
};

var command2 = new byte[25]
{
    0x03,0x00,0x00,0x19,0x02,0xf0,0x80,0x32,
    0x01,0x00,0x00,0xcc,0xc1,0x00,0x08,0x00,
    0x00,0xf0,0x00,0x00,0x01,0x00,0x01,0x03,0xc0
};
        
socket socket = new socket(addressfamily.internetwork, sockettype.stream, protocoltype.tcp);
socket.connect(new ipendpoint(ipaddress.parse(ip), port));

//第一次初始化指令交互
socket.send(command1);
var head1 = socketread(socket, siemensconstant.initheadlength);
socketread(socket, getcontentlength(head1));

//第二次初始化指令交互
socket.send(command2);
var head2 = socketread(socket, siemensconstant.initheadlength);
socketread(socket, getcontentlength(head2));

对寄存器的读取

我们在客户端电用iotclienttool读取地址v2634，抓取到包

我们可以看到其中很多都是固定的数据，如版本号、协议id等等。所以，我们可以以此规律获取对应的指令格式

protected byte[] getreadcommand(byte type, int beginaddress, ushort dbaddress, ushort length)
{
    byte[] command = new byte[31];
    command[0] = 0x03;
    command[1] = 0x00;//[0][1]固定报文头
    command[2] = (byte)(command.length / 256);
    command[3] = (byte)(command.length % 256);//[2][3]整个读取请求长度为0x1f= 31 
    command[4] = 0x02;
    command[5] = 0xf0;
    command[6] = 0x80;//cotp
    command[7] = 0x32;//协议id
    command[8] = 0x01;//1  客户端发送命令 3 服务器回复命令
    command[9] = 0x00;
    command[10] = 0x00;//[4]-[10]固定6个字节
    command[11] = 0x00;
    command[12] = 0x01;//[11][12]两个字节，标识序列号，回复报文相同位置和这个完全一样；范围是0~65535
    command[13] = 0x00;
    command[14] = 0x0e;//parameter length（[17]-[30]都为parameter刚好14也就是0x0e）
    command[15] = 0x00;
    command[16] = 0x00;//data length
    command[17] = 0x04;//04读 05写
    command[18] = 0x01;//读取数据块个数
    command[19] = 0x12;//variable specification
    command[20] = 0x0a;//length of following address specification
    command[21] = 0x10;//syntax id: s7any 
    command[22] = 0x02;//transport size: byte 
    command[23] = (byte)(length / 256);
    command[24] = (byte)(length % 256);//[23][24]两个字节,访问数据的个数，以byte为单位；
    command[25] = (byte)(dbaddress / 256);
    command[26] = (byte)(dbaddress % 256);//[25][26]db块的编号
    command[27] = type;//访问数据块的类型
    command[28] = (byte)(beginaddress / 256 / 256);
    command[29] = (byte)(beginaddress / 256);
    command[30] = (byte)(beginaddress % 256);//[28][29][30]访问db块的偏移量
    return command;
}

读取数据

public result<byte[]> readstring(string address, ushort length)
{
    connect();
    var result = new result<byte[]>(); 
    //发送读取信息
    var arg = convertarg(address);
    byte[] command = getreadcommand(arg.typecode, arg.beginaddress, arg.dbblock, length);
    result.requst = string.join(" ", command.select(t => t.tostring("x2")));
    var datapackage = sendpackage(command);
    byte[] requst = new byte[length];
    array.copy(datapackage, 25, requst, 0, length);
    //array.copy(datapackage, datapackage.length - length, requst, 0, length);
    result.response = string.join(" ", datapackage.select(t => t.tostring("x2")));
    result.value = requst; 
    return result;
}

对寄存器的写入

我们在客户端电用iotclienttool对地址v2634写入值666，抓取到包

我们可以以此规律获取对应的指令格式

protected byte[] getwritecommand(byte type, int beginaddress, ushort dbaddress, byte[] data)
{
    byte[] command = new byte[35 + data.length];
    command[0] = 0x03;
    command[1] = 0x00;//[0][1]固定报文头
    command[2] = (byte)((35 + data.length) / 256);
    command[3] = (byte)((35 + data.length) % 256);//[2][3]整个读取请求长度
    command[4] = 0x02;
    command[5] = 0xf0;
    command[6] = 0x80;
    command[7] = 0x32;//[4]-[7]固定数据
    command[8] = 0x01;//1  客户端发送命令 3 服务器回复命令
    command[9] = 0x00;
    command[10] = 0x00;
    command[11] = 0x00;
    command[12] = 0x01;//[9]-[12]标识序列号
    command[13] = 0x00;
    command[14] = 0x0e;
    command[15] = (byte)((4 + data.length) / 256);
    command[16] = (byte)((4 + data.length) % 256);//[15][16]写入长度+4
    command[17] = 0x05;//04读 05写
    command[18] = 0x01;//写入数据块个数
    command[19] = 0x12;
    command[20] = 0x0a;
    command[21] = 0x10;//[19]-[21]固定
    command[22] = 0x02;//写入方式，1是按位，2是按字
    command[23] = (byte)(data.length / 256);
    command[24] = (byte)(data.length % 256);//写入数据个数
    command[25] = (byte)(dbaddress / 256);
    command[26] = (byte)(dbaddress % 256);//db块的编号
    command[27] = type;
    command[28] = (byte)(beginaddress / 256 / 256 % 256); ;
    command[29] = (byte)(beginaddress / 256 % 256);
    command[30] = (byte)(beginaddress % 256);//[28][29][30]访问db块的偏移量
    command[31] = 0x00;
    command[32] = 0x04;//04 byte(字节) 03bit（位）
    command[33] = (byte)(data.length * 8 / 256);
    command[34] = (byte)(data.length * 8 % 256);//按位计算出的长度
    data.copyto(command, 35);
    return command;
}

写入数据

public result write(string address, byte[] data)
{
    if (!socket?.connected ?? true) connect();
    result result = new result(); 
    array.reverse(data);
    //发送写入信息
    var arg = convertarg(address);
    byte[] command = getwritecommand(arg.typecode, arg.beginaddress, arg.dbblock, data);
    result.requst = string.join(" ", command.select(t => t.tostring("x2")));
    var datapackage = sendpackage(command);
    result.response = string.join(" ", datapackage.select(t => t.tostring("x2")));
    return result;
}

iotclient中s7-200smartcp协议的使用

安装

nuget安装 install-package iotclient
或图形化安装

使用

//1、实例化客户端 - 输入正确的ip和端口
siemensclient client = new siemensclient(siemensversion.s7_200smart, "127.0.0.1",102);

//2、写操作
client.write("q1.3", true);
client.write("v2205", (short)11);
client.write("v2209", 33);

//3、读操作
var value1 = client.readboolean("q1.3").value;
var value2 = client.readint16("v2205").value;
var value3 = client.readint32("v2209").value;

//4、如果没有主动open，则会每次读写操作的时候自动打开自动和关闭连接，这样会使读写效率大大减低。所以建议手动open和close。
client.open();

//5、读写操作都会返回操作结果对象result
var result = client.readint16("v2205");
//5.1 读取是否成功（true或false）
var issucceed = result.issucceed;
//5.2 读取失败的异常信息
var errmsg = result.err;
//5.3 读取操作实际发送的请求报文
var requst  = result.requst;
//5.4 读取操作服务端响应的报文
var response = result.response;
//5.5 读取到的值
var value3 = result.value;

结束

• 同步至索引目录：《物联网基础组件iotclient开发系列》
• 参考:
• 完整实现：https://github.com/zhaopeiym/iotclient