====== TransSECS Host: How to Build and Use the Digital Twin ======

===== What Is the Digital Twin in TransSECS? =====
In TransSECS, a Digital Twin is a snapshot of the tool’s model as captured during the project build. It provides a read-only, simulation-ready copy of the tool interface, separate from any host-side modifications.

The **DT (Digital Twin)** becomes a tool simulator that you can use to test your host project, as you build and test the host you are making.

===== What Exactly Is Saved as the Digital Twin? =====
When a project is built, TransSECS automatically creates a folder under the project named:  
**<ProjectName>DigitalTwin**

This folder contains copies of key project files, but those files reflect the tool model — not the host-side logic.  
Although the structure may resemble the main project, the content is frozen at build time and used strictly for simulation and validation — not for active host logic.

===== Why It Looks Like a Project Copy =====
The Digital Twin folder contains familiar .xml and config files. However:

  * It is a mirror of the tool-side configuration  
  * It does not reflect host-side JavaScript, triggers, or logic  
  * It is not modified by later project updates — making it ideal for regression testing  

Think of it as a preserved **“Tool View”** snapshot — perfect for comparing against evolving host implementations.
{{ :transsecs_host:pasted:20250731-103633.png?400|}}

===== Where Is the Digital Twin Stored? =====
The Digital Twin folder is created automatically under your project directory at build time. It remains intact even if you later:

  * Delete CEIDs or reports  
  * Modify variable mappings  
  * Adjust host scripts  

This allows you to roll back or validate changes against the original tool definitions.

===== Why Use the Digital Twin? =====
The Digital Twin enables you to:

  * Simulate tool behavior without a live connection  
  * Reproduce mismatches between tool and host CEIDs/SVIDs  
  * Test robustness against unknown or unexpected events  
  * Compare changes across project versions  
  * Debug and regression test with confidence  

===== Example of Use Case Workflow =====
  - Build the project with the live tool or a tool file  
  - TransSECS automatically saves the Digital Twin  
  - Modify the host project — e.g., delete certain CEIDs  
  - Test using the preserved tool model to simulate missing or extra events  
  - Analyze the host’s behavior and ensure it gracefully handles mismatches  

===== Summary =====
The TransSECS Digital Twin is a powerful and convenient feature that:

  * Captures the tool’s interface model at build time  
  * Preserves the original CEIDs, VIDs, reports, and metadata  
  * Enables offline simulation, testing, and validation  
  * Supports version control, comparison, and error scenario emulation  

No setup is required — the Digital Twin is created automatically.  
For engineers developing and refining SECS/GEM host logic, it is an essential tool for building reliable, robust systems.