Integrations (PTC products, 3rd party products and code) > Code integration (Ada, ARINC 653, C, C#, C++, IDL, Java, SQL and VB) > Transformation Development Kit (TDK) > Working with TDK > Enabling and disabling reverse engineering (TDK)
  
Enabling and disabling reverse engineering (TDK)
For TDK Code Generation Transformation Patterns models, we recommend that you disable reverse engineering.
For TDK 3G models and TDK Legacy models, TDK can optionally reverse engineer changes made to generated SDL files. In addition, TDK can optionally reverse engineer relevant changes to generated SDL files on Startup. Although you can reverse engineer changes made to SDL files, we recommend that you maintain your generation templates in the TDK model.
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If the Reverse on Startup check box is selected and you disable reverse engineering through the Enable or Disable Reverse Engineering toolbar button, ACS clears the Reverse on Startup check box.
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Do not change the same reversible properties in both Modeler and the code while TDK is not running. The changes in the TDK model or SDL files will be lost when TDK is started.
To enable or disable reverse engineering:
• On the ACS/TDK Control toolbar, click the Enable or Disable Reverse Engineering button.
Reverse is enabled when the Reverse button is depressed.
To enable or disable reverse engineering on startup:
1. On the ACS/TDK Control toolbar, click the Edit ACS Settings button.
2. On the ACS/TDK Settings dialog, select or clear the Reverse on Startup check box.