Decompiling the NC Database Using the UNDDL Command - Metasys - LIT-12011829 - Field Device - VMA18 VAV Modular Assembly

N2 VMA Application Note

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VMA18 VAV Modular Assembly
Document type
Application Note
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This section describes how to use the UNDDL command to decompile the NC database and how to check the database for errors.

To decompile the NC database:

  1. Open a command prompt window.
  2. Change the current directory to the FMSDATA path.
  3. Decompile the NC database.
  4. Type the following command string to overwrite the existing file contents: C:\>UNDDL NC <NETWORK NAME> <NCNAME> /Y. See Figure 1 for an example command string.
    Figure 1. Command Prompt Decompile Command

  5. Once the decompile process is complete, a file with a UND extension appears in the <NCNAME> folder and the subdirectory.
    Note: If the decompile is successful, no errors should be present. If errors are present, as in Figure 2, correct them using a text editor. Errors are indicated by the tilde (~) character and are searchable in the text editor.
    Figure 2. Command Prompt Decompile Errors

  6. Copy the <NCNAME>.und file to the <NCNAME>.ddl file.
  7. Open the NC-1.ddl file in a text editor.
  8. In the <NCNAME>.ddl file, locate the definition of the VMA14xx controller that you want to replace.
  9. Fix any errors discovered during the decompile.
  10. Change the device type for the VMA from "VMA" to "VND" (Figure 3).
    Figure 3. Change Device Type

  11. Change the model name for any CS objects associated with the VMA1832 controller to use the new model name from the model file (Figure 4).
    Note: The model name in Figure 4 must change from "VAV-CLG" to "1420-SD" to match the model created in Figure 1.
    Figure 4. Change Model Name

  12. Save the model file.
  13. Open the PRN file created by CCT for the new controller application. Review the point list and attributes of the copied CS model and compare its point list with the PRN file of the VMA1832 controller. Most of the points in your copied model should match points in the PRN file.