OPC-UA Interface Guide (Smart Connectivity)

Smart Print Controller v5.5.0.8498, Copyright (c) 2023 Global Graphics Software. All rights reserved.

Overview

Smart Print Controller provides a user with two conceptual methods of operations:

1. Engineer - Installation and setup.
2. Operator - Manage job submission and review progress.

This 'operator' level of operation can be driven from external clients using an industry-standard interface.

When the Open Platform Communications (OPC) server in Smart Print Controller is enabled an OPC node tree is published. The top-level nodes in this tree represent grouped areas of state and functionality. For example, the Servers section allows:

• the RIP Server list to be enumerated.
• the server connection status to be examined.
• all servers to be restarted.
• ...and more.

Certificates

Communication between OPC UA clients and servers require both parties to possess their own application certificate. To enable further communication each party must trust the opposing certificate. This trust can be established automatically, programmatically or manually depending on the application's configuration or implementation. The certificate for Smart Print Controller can be found in %programdata%\Global Graphics Software Ltd\Smart Print Controller\App Certificates\certs should you need to copy it to the Trusted Peer Certificate folder. In this release it is a Self Signed Certificate issued by and for Smart Print Controller.

OPC Nodes

The OPC node mechanism will report when any state changes, allowing clients to react accordingly.

While most exposed values can be read by a client, write-access (or calling a method to request a state change in Smart Print Controller) requires External Control to be granted (See App.IsExternalControlActive). This is an action explicitly performed by the Smart Print Controller operator, resulting in control of the application to be given to the OPC client.

Server Mode

If Smart Print Controller is launched with a /ServerMode command-line argument the application will be launched minimized, with OPC automatically enabled and External Control granted. Additionally, /Silent will disable the application splash screen and any taskbar messages that would otherwise be displayed.

Setting App.ServerModeLocked will ensure the application window stays minimized, with no option to be restored to the screen.

OPC Methods

Many published OPC method nodes return a String value indicating their success or error state. In all such cases a check for Success indicates success, and any other value indicates an error.

Any methods returning data (for example JSON or comma-separated values) will be explicitly documented. Callers should validate returned data format to determine success (otherwise one of the above errors may be returned).

Any methods listed in this documentation include details about required parameters (if any) and return values.

In the event of an error, please see the Smart Print Controller log file for more information.

OPC Client Library

The following documentation provides guidance on using the Traeger Industry Components GmbH OPC client library for software developers working with Smart Print Controller.

Configuring Custom Message Sizes

The default maximum message sizes used by OPC clients to communicate to the server are sufficient for most use cases. However, to ensure transfer of larger data packets it may be necessary to configure the OPC client with custom values.

For example:

	Client = new OpcClient();
	Client.Transport.MaxArrayLength = 1024 * 1024 * 50;
	Client.Transport.MaxBufferSize = 1024 * 1024 * 50;
	Client.Transport.MaxMessageSize = 1024 * 1024 * 50;
	Client.Transport.MaxStringLength = 1024 * 1024 * 50;

See here for more information.

Adjusting Communication Timeouts

OPC clients regularly verify the responsiveness of the connection to the OPC server. However, in certain circumstances where the system is under heavy load, maintaining a responsive connection might not always be possible. To mitigate potential issues under such conditions, it is recommended to increase the default communication timeouts.

The example below demonstrates how to adjust the default values:

	var defaultTimeOut = (int)TimeSpan.FromMinutes(10).TotalMilliseconds;
	Client = new OpcClient
	{
	    // Don't auto-disconnect - Dispose the client to explicitly disconnect.
	    DisconnectTimeout = int.MaxValue,
	    KeepAlive = { Interval = defaultTimeOut },
	    SessionTimeout = defaultTimeOut,
	    OperationTimeout = defaultTimeOut,
	    ReconnectTimeout = defaultTimeOut
	};

Please note that the provided examples serve as illustrations, and it's important to tailor the configuration to your specific requirements.

SPCSet

SPCSet is the top-level set containing all available OPC nodes. Immediately underneath this root-level node are a categorized collection of sub-nodes, each encapsulating a different area of behavior.

ActiveJob

State relating to the currently active job.

Properties

ActiveMedia

State relating to the currently active media.

Details

The active media is the one actually being used to print.
The selected media (See AllMedia.SelectedName) is the one highlighted in the application UI.

Properties

AllJobs

State relating to all jobs in the Waiting/Print/Completed queues. This tree dynamically includes children named from the GUID of each known job.

Details

These OPC nodes are fully populated to a consistent state when the OPC server starts, apart from job GUIDs - These nodes are dynamically added and removed as jobs are added and removed to/from the workflow.
(If there are already jobs in the workflow, these GUIDs will exist when the OPC server starts.)

When a job is added to the Waiting queue a GUID node is created containing the job information (containing the same tag names as the ActiveJob node) and that GUID is added to the WaitingQueue array.
The job keeps the same GUID as is travels through the system, moving between the WaitingQueue, PrintQueue, and CompletedQueue arrays.

The GUID node is removed when the job is removed from the workflow.

See the SingleJob section for a description of all available job-level nodes.

Properties

Methods

AllMedia

State relating to all available media.

Properties

Methods

Files

NOTE OPC File nodes contain functions which allow access to file content:

• Open(int fileAccess) - Open the file with the specified fileAccess (1:read, 2:write), returning an integer file handle.
• Read(int fileHandle, int length) - Read data from an open file handle, returning an array of bytes.
• Write(int fileHandle, byte[] buffer) - Write/append data to an open file handle.
• Close(int fileHandle) - Close the file handle after use.

For more information see the OPC documentation.

AllMedia.SelectedMedia

State relating to the selected media (See AllMedia.SelectedName).

Details

Note that when setting new media properties the changes are set in the Smart Media immediately, but changes must be applied using App.ApplySettings() before they take effect on the server(s).

Properties

Methods

App

State relating to the entire application.

Details

Some features (such as job costing) require the use of an offline service RIP, allowing for background processing while other job actions are active.
If any RIP servers are currently defined to use 127.0.0.1, the service RIP will not be available (See OpcServiceRip).

Properties

Methods

Files

NOTE OPC File nodes contain functions which allow access to file content:

• Open(int fileAccess) - Open the file with the specified fileAccess (1:read, 2:write), returning an integer file handle.
• Read(int fileHandle, int length) - Read data from an open file handle, returning an array of bytes.
• Write(int fileHandle, byte[] buffer) - Write/append data to an open file handle.
• Close(int fileHandle) - Close the file handle after use.

For more information see the OPC documentation.

JobCosting

State relating to job cost estimation.

Details

Job cost estimation requires the use of a local service RIP, allowing for background processing while other job actions are active.
Changes to the state in this section are immediate and do not require an explicit 'Apply' action.

To generate a cost report from an SPC-queued job, call ProcessJob().
If successful, the JSON result will either be stored in the job's JobCostData property or in AvailableResults (depending on the parameters passed to ProcessJob()).
If the latter, the AvailableResults array will be updated once processing is complete, and a call to GetReportData() may be performed.
If the job succeeds, GetReportData() will return a JSON string.
If the job fails, GetReportData() will return an empty string.
If the job is cancelled (CancelJobFile()), the AvailableResults array will not be updated, and GetReportData() will not be required.

A scheduled job can be cancelled at any time by calling CancelJobFile().

External control is not required for job costing actions to be performed.
Clients may call App.SetClientIsBusy() to let SPC know its job costing feature is being used.

Properties

Methods

Memory

State relating to available memory on the local machine and the memory required for the local RIP to function.

Properties

PageSubmitter

State relating to the optional PageSubmitter plugin.

Details

Automatically splits multi-page PDFs into smaller jobs for printing

This feature allows submission of specific page ranges from a single PDF file. Instead of printing an entire document at once, it can be split into separate print jobs.
For example, pages 1-5, pages 6-10, and so on. Each page range becomes its own job in the Waiting queue, making it easier to manage large documents or prioritize specific sections for printing.

Properties

Methods

PrintBarGroups

State relating to the active print bars.

Details

Note that each print bar 'group' corresponds to a collection of print bars which use the same settings (BPP, resolution, etc).

Properties

Methods

PrinterProfile

State relating to the active printer profile.

Properties

Methods

PrintRun

State relating to the print run.

Properties

Methods

PrintRunConfig

State relating to the print configuration (Applies to both media sides).

Properties

PrintRunConfig.ConfigSideA

The print configuration specific to media side 'A'.

Properties

PrintRunConfig.ConfigSideB

The print configuration specific to media side 'B'.

Properties

Servers

State relating to the collection of RIP Servers.

Properties

Methods

Files

NOTE OPC File nodes contain functions which allow access to file content:

• Open(int fileAccess) - Open the file with the specified fileAccess (1:read, 2:write), returning an integer file handle.
• Read(int fileHandle, int length) - Read data from an open file handle, returning an array of bytes.
• Write(int fileHandle, byte[] buffer) - Write/append data to an open file handle.
• Close(int fileHandle) - Close the file handle after use.

For more information see the OPC documentation.

ServiceRip

State relating to the offline Service RIP.

Details

The Service RIP provides functionality, including offline processing of jobs by rendering PDF pages into a contone image format for external manipulation and then re-embedding those images back into the original PDF.

The RipToContone() method is used to render each page of a PDF into a series of colorant-based contone TIFF images, which can be modified externally.
The EmbedContone() method re-embeds the modified images into the original PDF. The TIFF images and an accompanying job XML file (from RipToContone()) must be located in the specified input folder.

It is also possible to generate a PDF containing screened separations, allowing close examination of the output that would otherwise be sent to a press. See RipToScreenedPdf() for details.

This system enables asynchronous job processing, meaning jobs are queued and results are available later for retrieval. Clients can monitor the completion of these jobs via AvailableResults and retrieve detailed result data using GetResultData().

If any RIP servers are currently using 127.0.0.1, the Service RIP will not be available.

Clients may call App.SetClientIsBusy() to let SPC know its offline services are being used.

Properties

Methods

SingleJob

Describes the collection of nodes representing a single job, positioned as a child of the WaitingQueue, PrintQueue, or CompletedQueue nodes.

Properties

StreamlineDirect

State relating to Streamline Direct technology.

Properties

WaitingQueueOptions

State relating to the behavior of the Waiting queue.

Properties