It is intended for software developers of machine manufacturers who integrate, validate, and operate the library function blocks within CODESYS-based applications.

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Further information can be found under: https://www.ddas.digital

1.1 Document history

Version			Description
1.0	14.04.2026	DDAS	Initial version

2 General

2.1 Library

This library manages the library licensing mechanism.

The library includes the following user function block:

Get_Lib_License

Detailed descriptions of the function blocks and their relevant dependencies are provided in the following chapters.

2.2 Licensing Concept

All libraries require a valid license. Each license is based on three mandatory keys:

SiteCode
Provided by the user (e.g. ‘DDAS-Site-License’)
LibraryGuid
Delivered with the library (e.g. ‘{LIB-DDAS-D5BA612E}’)
LibraryActivationKey
Issued by DDAS (e.g. ‘EDB86DA0’)

License Activation Mechanism

To activate a library license, one instance of the function block Get_Lib_License must be called for each licensed library.
This function block is part of the DDAS_LicenseManager_Lib library.

Licensing Process

The following steps are required to license and use a library:

The user selects the required libraries.
The user integrates the selected libraries into a test project or uses the provided demo program and evaluates them using the time‑limited demo license.
If the user intends to use the library function blocks in a machine application, the library is ordered and the selected SiteCode is sent to DDAS.
DDAS provides the corresponding LibraryActivationKey.
In the machine application, the user instantiates the function block Get_Lib_License once for each library and assigns all required license keys to activate the library license.
After successful activation, all function blocks of the licensed library can be implemented and executed.

Note: Detailed information on how to use the function block Get_Lib_License is provided in this software manual.

Note: The function Get_eError is available in every library and provides access to the error enumeration corresponding to a function block’s error code, when required.

Demo Visualisation

3 FB Get_Lib_License

3.1 General Information

This chapter describes the function block Get_Lib_License.

Function Block Name: Get_Lib_License

Library: DDAS_LicenseManager_Lib

Dependent Codesys libraries: none

CODESYS Version Compatibility: CODESYS V3.5 and higher

License / Usage Restrictions: Requires valid full or demo library license

3.2 Purpose & Scope

The Get_Lib_License function block manages the library licensing mechanism. A separate instance of this function block is required for each DDAS library used within an application.

The function block is designed to activate the library license for all function blocks contained in a specific DDAS library. Each DDAS library inherits the DDAS_LicenseManager_Lib; however, this library must be explicitly added to the user’s machine application in order to enable license activation.

Typical Use Cases

· Activate licenses for all function blocks within a DDAS library

3.3 Functional Overview

When enabled, the Get_Lib_License function block activates the full library license or manages the operation of a time‑based demo license.

It outputs:
- Full license active
- Demo license active
- Time left of demo license

A demo license is valid for a duration of 2 hours. After this time has elapsed, no active license is available, and all function blocks of the library enter an idle state.

To reactivate the demo license, the controller must be restarted. Each controller restart reactivates the demo license and starts a new demo period.

Error states are monitored continuously and reported via diagnostic outputs.

3.4 Interface Description

3.4.0 Function block Inputs and Outputs

Scope	Name	Type	Comment
Input	xEnabled	BOOL	When TRUE, license management is executed cyclically.
	sSiteCode	STRING	Please assign the Company Site Code.
	sLibraryGuid	STRING	Please assign the Library Guid Code.
	sLibraryActivationKey	STRING	Please assign the Library Activation Code .
Output	xFullLicensed	BOOL	TRUE valid full License
	xDemoActive	BOOL	TRUE when demo License
	tTimeLeft	TIME	Display left time in demo mode
	xLicensed	BOOL	TRUE when a valid full or demo library license is active.
	xError	BOOL	TRUE if an error or warning is detected. Detailed error information is provided in iErrorID.
	iErrorID	INT	Error and status identifier for diagnostics.

3.4.1 Enumerations

eError

Library Possible Error Codes and Descriptions.

Name	Initial	Comment
no_error	0	No Error detetced
empty_Key	10	Activation Key string is empty
empty_SiteCode	11	Site code string is empty
empty_cLibraryGuid	12	Library guide code string is empty, no demo license available
invalid_Key_size	20	Invalid Activation Key string size, 8 char required
invalid_Key	21	Invalid Activation Key string
demo_License_expired	30	Demo license has been expired, system restart required

3.5 Execution & Timing Behaviour

The function block is intended to be executed cyclically in a task context.

Timing precision depends on the configured task cycle time and target platform

3.6 Error Handling & Diagnostics

If an internal error, a library issue, or a licensing problem occurs, xError is set to TRUE and iErrorID provides the corresponding error code. Detailed descriptions of the error codes are defined in the enumeration eError.

3.7 Assumptions & Limitations

This library serves as an extension to all DDAS libraries and is applicable only within the DDAS library ecosystem.

3.8 Example Implementation

Declaration and Call of the Function Block Get_Lib_License:

VAR

fb_GetLibLicense: DDAS_LM.Get_Lib_License;

END_VAR

FB call in structure text:

fb_GetLibLicense(

xEnabled := TRUE,

sSiteCode:= 'DDAS-Site-License',

sLibrayGuid := '{LIB-DDAS-D5BA612E}'

sLibraryActivationKey := ‘EDB86DA0’

);

FB call in continuous function chart diagram:

Demo Visualisation

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