MewtocolNet

An easy to use Mewtocol protocol library to interface with Panasonic PLCs over TCP/Serial.

⚠️ This library is not an official panasonic product nor does panasonic provide financial support or limitations in any form. This software was written by WOLF Medizintechnik GmbH (@WOmed/dev).

PLC Support

For a full list check this table

This library was only tested with a few PLCs, other types that support the Panasonic Mewtocol protocol might work. Use at your own risk, others might follow with community feedback

Features

Fully implemented

• TCP/IP and Serial Port support
• Get type and hardware information of PLCs
• Get PLC program metadata such as program version and IDs
• Read and write registers in real time
• Basic data types / structures support
• Fast readback cycles due to a MemoryManager that optimizes TCP / Serial frames by combining areas
• Fully customizable heartbeats and polling levels (tell the interface when you need register updates)
• Easy to use builder patterns for interface and register generation
• Register type casting from property attributes
• Change RUN / PROG modes
• Delete Programs
• Write / read low level byte blocks to areas
• Scanning for network devices and change network settings (WDConfigurator features)

Planned

• Upload / Download programs to the PLC
• Reading / writing PLC system registers
• Advanced data structures like SDTs and SDT Arrays
• Custom open source program compiler for PLC cpus

Support

.NET Support

This library was written in netstandard2.0 and should be compatible with a lot of .NET environments.

For a full list of supported .NET clrs see this page

Installation

Use the dotnet CLI and run

dotnet add package Mewtocol.NET

Protocol description

Panasonic has published a protocol definition on their site. Refer to this site if you want to see the general functionality or add / report missing features.

This library is at the time not feature complete, but all essential features are provided

Examples

To see a full list of examples click here.

Connecting to a PLC

Connecting to a PLC is as simple as

using MewtocolNet;

using (var plc = Mewtocol.Ethernet("192.168.178.55").Build()) {

    await plc.ConnectAsync();
    if (!plc.IsConnected) {
        Console.WriteLine("Failed to connect to the plc...");
    } else {
        Console.WriteLine(plc.PlcInfo);
    }

}

Reading data registers / contacts

Detailed instructions

• Create a new class that inherits from RegisterCollection

using MewtocolNet;
using MewtocolNet.RegisterAttributes;

public class TestRegisters : RegisterCollection {

    //corresponds to a R100 boolean register in the PLC
    [Register("R100")]
    public bool TestBool1 { get; private set; }

    //corresponds to a XD input of the PLC
    [Register("XD")]
    public bool TestBoolInputXD { get; private set; } 

    //corresponds to a DDT7012 - DDT7013 as a 32bit time value that gets parsed as a timespan (TIME)
    //the smallest value to communicate to the PLC is 10ms
    [Register("DDT7012")]
    public TimeSpan TestTime { get; private set; }  
    
    //corresponds to a DT1101 - DT1104 string register in the PLC with (STRING[4])
    [Register("DT1101", "STRING[4]")]
    public string TestString1 { get; private set; }

}

• Connect to the PLC and attach the register collection and logger
• attach an automatic poller by chaining .WithPoller() after the register attachment

TestRegisters registers = null;

//setting up a new PLC serial interface and tell it to use the register collection
var plc = Mewtocol.Serial("COM4", BaudRate._19200)
.WithPoller()
.WithRegisterCollections(c => {
    registers = c.AddCollection<TestRegisters>();
    // or use
    // c.AddCollection(new TestRegisters());
    // if you want to pass data to a constructor
})
.Build();

//connect to it
await plc.ConnectAsync(async () => {

    //restart the plc program during the connection process
    await plc.RestartProgramAsync();

});

//wait for the first data cycle of the poller module
//otherwise the property value might still be unset or null
await App.ViewModel.Plc.AwaitFirstDataCycleAsync();

if (App.ViewModel.Plc.IsConnected) {

    Console.WriteLine(registers.TestBool1);

}

• Your properties are getting automatically updated after the initial connection

Note! this is not your only option to read registers, see here

Reading & Writing

In addition to the automatic property binding you can use these patterns:

Reading & Writing by using the anonymous builder pattern

await plc.Register.Struct<short>("DT100").WriteAsync(100);

var value = await plc.Register.Struct<short>("DT100").ReadAsync();

Reading & Writing by using the direct reference from the builder pattern

IRegister<bool> outputContactReference;

var plc = Mewtocol.Ethernet("127.0.0.1")
.WithRegisters(b => {

    b.Bool("Y4").Build(out outputContactReference);

})
.Build();

await plc.ConnectAsync();

await outputContactReference.WriteAsync(true);