QNet-SDK is a set of software interfaces (API), libraries, programs and demos released with Qworkbench or QResourcesManager.
It provides an easy way to develop PC applications including communication with Qem devices that are connected with QNet for third-party software developers.

QNet is a network used to connect Qem devices.
It use a software called QRM (Qem Resources Manager) to manage connection resources.

To be used the QNet-SDK require that the Qworkbench or QResourcesManager is properly installed either in development computer and in final user computer.

QNet implements the concept of distribution and de-localization of connection services, in this way it is possible to achieve a local or remote Qem device exactly the same way, making the implementation of a communication program and its use really very simple.

QNet is composed by many parts listed below:

• The nodes.
• The QNet cloud.
• The Qem devices.
• The resources ID.
• The signatures keys.
• The API interfaces to connect all.

Follow a representative image of entire system:

A node is an execution instance of the QRM program or a QBR1A device.
A node is identified by a special ID in the cloud.
A node can be connected or disconnected from the cloud.
In the cloud, there may be multiple nodes simultaneously.
In the cloud the nodes are visible only when connected.

A resource is an access point to communicate with a Qem device in which all connection parameters with the same are specified.
A node has a list of local resources and if connected to the cloud can access the public resources of other nodes connected to the cloud.
A node is called local when accessed directly via its IP address: Port.
A node is called remote when accessed, from a local node, using the capabilities of the cloud.

SignalCode

CpuState

The Active property can be used to get state of connection channel between ClientNode01 object and QRM server pointed to the TCP/IP port defined with Host and Port properties.

The Host property is used to define in what IP address the QRM TCP/IP server is listening for a connection with ClientNode01.

The default value is 'localhost' aka '127.0.0.1', but is possible to reach any QRM available in a public WAN/LAN address.
The Host property SHOULD be set BEFORE to set Active to True or call OpenConnection() method.
The Host property can be either numeric IP string or an URL (that require a DNS server running).

The Port property is used to define in what IP port the QRM TCP/IP server is listening for a connection with ClientNode01.

The default value is 3000, but is possible to reach any QRM available in a public WAN/LAN address using any different port.
The Port property SHOULD be set BEFORE to set Active to True or call OpenConnection() method.

In the ErrorCode property is stored the SignalCode result value from last API method call..

In the ErrorMessage property is stored the description text of SignalCode result value from last API method call.

The ProjectChecksumCode property contains the code checksum stored in SYM file loaded using LoadFromFile() method.

The ProjectChecksumConfiguration property contains the configuration checksum stored in SYM file loaded using LoadFromFile() method.

The ProjectChecksumSources property contains the sources checksum stored in SYM file loaded using LoadFromFile() method.

The ProjectChecksumSymbols property contains the symbols checksum stored in SYM file loaded using LoadFromFile() method.

The TargetChecksumCode property contains the code checksum stored in Target CPU loaded using OpenConnection() method.

The TargetChecksumConfiguration property contains the configuration checksum stored in Target CPU loaded using OpenConnection() method.

The TargetChecksumSources property contains the sources checksum stored in Target CPU loaded using OpenConnection() method.

The TargetChecksumSymbols property contains the symbols checksum stored in Target CPU loaded using OpenConnection() method.

The OpenConnection method is used to open a connection with a Qem device somewhere in the cloud using its Resource ID.

A Resource ID is a string data which can be obtained clicking with right mouse key upon resource name in the QRM resource list and choosing the menu 'Copy Resource ID to Clipboard'.
At this point in the Clipboard you will have a string like that: {E5F1E5D9-A909-41D4-A89D-0374C83E6163}. Well done. This is a Resource ID !

SignalCode OpenConnection([in] BSTR ResourceID);

PS: remember Resource ID is a UNIQUE ID so there will be no other resources with the same ID in all the cloud.

PS: OpenConnection try implicitly to put Active property to True if is in False state, where CloseConnection try implicitly to put Active property to False if in True state.

The CloseConnection method is used to close an opened connection with a Qem device somewhere in the cloud.

SignalCode CloseConnection();

SignalCode CheckConnection();

SignalCode LoadFromFile([in] BSTR FileName);

SignalCode ReadSimple([in] BSTR SymbolName, [in, out] BSTR* Value);

SignalCode ReadArray([in] BSTR ArrayName, [in] long Index, [in, out] BSTR* Value);

SignalCode ReadArrayRange([in] BSTR ArrayName, [in] long Index, [in] long Elements, [in, out] VARIANT* Values);

SignalCode ReadDGDataProgram([in] BSTR SymbolName, [in] long ProgIndex, [in, out] BSTR* Value);

SignalCode ReadDGStep([in] BSTR SymbolName, [in] long ProgIndex, [in] long StepIndex, [in, out] BSTR* Value);

SignalCode ReadDevice([in] BSTR DeviceName, [in] BSTR SymbolName, [in, out] BSTR* Value);

SignalCode WriteSimple([in] BSTR SymbolName, [in] BSTR Value);

SignalCode WriteArray([in] BSTR ArrayName, [in] long Index, [in] BSTR Value);

SignalCode WriteArrayRange([in] BSTR ArrayName, [in] long Index, [in] long Elements, [in] VARIANT Values);

SignalCode WriteDGDataProgram([in] BSTR SymbolName, [in] long ProgIndex, [in] BSTR Value);

SignalCode WriteDGStep([in] BSTR SymbolName, [in] long ProgIndex, [in] long StepIndex, [in] BSTR Value);

SignalCode WriteDevice([in] BSTR DeviceName, [in] BSTR SymbolName, [in] BSTR Value);

Will follow the IDL representation of ClientNode Interface to use if you would like to manually access it with IDispatch.

[
  uuid(A58FB5BD-8704-4746-AC0D-B9F34701BC4A),
  version(1.0),
  helpstring("Dispatch interface for ClientNode01 Object"),
  dual
]
dispinterface IClientNode01 {
  properties:
  methods:
      [id(0x000000c9), propget]   VARIANT_BOOL Active();
      [id(0x000000c9), propput]   void Active([in] VARIANT_BOOL rhs);
      [id(0x000000ca), propget]   BSTR Host();
      [id(0x000000ca), propput]   void Host([in] BSTR rhs);
      [id(0x000000cb), propget]   long Port();
      [id(0x000000cb), propput]   void Port([in] long rhs);
      [id(0x000000cc)]            SignalCode LoadFromFile([in] BSTR FileName);
      [id(0x000000ce), propget]   long ProjectChecksumCode();
      [id(0x000000cd), propget]   long ProjectChecksumConfiguration();
      [id(0x000000cf), propget]   long ProjectChecksumSources();
      [id(0x000000d0), propget]   long ProjectChecksumSymbols();
      [id(0x000000d1), propget]   long TargetChecksumCode();
      [id(0x000000d2), propget]   long TargetChecksumConfiguration();
      [id(0x000000d3), propget]   long TargetChecksumSources();
      [id(0x000000d4), propget]   long TargetChecksumSymbols();
      [id(0x000000d5)]            SignalCode OpenConnection([in] BSTR ResourceID);
      [id(0x000000d6)]            SignalCode CloseConnection();
      [id(0x000000d7)]            SignalCode CheckConnection();
      [id(0x000000d8)]            SignalCode ReadSimple([in] BSTR SymbolName, [in, out] BSTR* Value);
      [id(0x000000d9)]            SignalCode ReadArray([in] BSTR ArrayName, [in] long Index, [in, out] BSTR* Value);
      [id(0x000000da)]            SignalCode ReadDGDataProgram([in] BSTR SymbolName, [in] long ProgIndex, [in, out] BSTR* Value);
      [id(0x000000db)]            SignalCode ReadDGStep([in] BSTR SymbolName, [in] long ProgIndex, [in] long StepIndex, [in, out] BSTR* Value);
      [id(0x000000dc)]            SignalCode ReadDevice([in] BSTR DeviceName, [in] BSTR SymbolName, [in, out] BSTR* Value);
      [id(0x000000dd)]            SignalCode WriteSimple([in] BSTR SymbolName, [in] BSTR Value);
      [id(0x000000de)]            SignalCode WriteArray([in] BSTR ArrayName, [in] long Index, [in] BSTR Value);
      [id(0x000000df)]            SignalCode WriteDGDataProgram([in] BSTR SymbolName, [in] long ProgIndex, [in] BSTR Value);
      [id(0x000000e0)]            SignalCode WriteDGStep([in] BSTR SymbolName, [in] long ProgIndex, [in] long StepIndex, [in] BSTR Value);
      [id(0x000000e1)]            SignalCode WriteDevice([in] BSTR DeviceName, [in] BSTR SymbolName, [in] BSTR Value);
      [id(0x000000e2), propget]   SignalCode ErrorCode();
      [id(0x000000e3), propget]   BSTR ErrorMessage();
      [id(0x000000e4)]            SignalCode ReadArrayRange([in] BSTR ArrayName, [in] long Index, [in] long Elements, [in, out] VARIANT* Values);
      [id(0x000000e5)]            SignalCode WriteArrayRange([in] BSTR ArrayName, [in] long Index, [in] long Elements, [in] VARIANT Values);
      [id(0x000000E6)]            CpuState GetCpuState();      
};

Will follow in this chapter some simple samples to understand how to use the QNet-SDK interfaces.
The QNet-SDK interfaces can be used with any programming language and IDE which support the COM specification and specifically the IDispatch interface.
For the following samples was used a 32 bit Windows 7 machine with Microsoft Visual Studio Express 2012 and the Visual Basic.NET language.
The tool is freely downloadable from following link link.

Is not goal of these pages “to be guide” on how use IDE and COM interfaces in programming language which are you are used to.

Before to be used the QNet-SDK API Library need to be imported in the develop environment following next steps:

1. Open a new Visual Basic 2012 project called FirstSteps.
2. Rename default form name from Form1 to DesktopView to be aligned with next following instructions.
3. Import library using menu item “PROJECT→Add Reference…→COM→Type Libraries” and select QNet Access Library 1.0 like showed below:
   
   
   
   
4. Open DesktopView code editor and add:
   
   

   • Object reference declaration
     To be used in the program the ClientNode01 interface need to be supported by an object reference with :
     
     

           ClientNode As QNetAccessLibrary01.ClientNode01

   • Object creation
     In some initialization place, like the main class constructor, creates the ClientNode01 object with :
     
     

           ' Create ClientNode object
           ClientNode = New QNetAccessLibrary01.ClientNode01

   • Release object
     In some finalization place, like the main from closed event, release ClientNode01 object with :
     
     

           ' Free ClientNode object
           ClientNode = Nothing

At the end of these steps you should have something like:

Public Class DesktopView
 
    Private ClientNode As QNetAccessLibrary01.ClientNode01
 
    Public Sub New()
 
        ' This call is required by the designer
        InitializeComponent()
 
        ' Create and initialize ClientNode object
        ClientNode = New QNetAccessLibrary01.ClientNode01
 
    End Sub
 
    Private Sub DesktopView_FormClosed(sender As Object, e As FormClosedEventArgs) Handles MyBase.FormClosed
 
        ' Free ClientNode object
        ClientNode = Nothing
 
    End Sub
 
End Class

This is actually the minimal skeleton required to start to work with QNet-SDK.
Next step involves to load Qmove project symbols files and operations required to read and write any type of Qmove variables.