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How to Load Lisp in AutoCAD 2021

Understanding AutoLISP for AutoCAD

AutoLISP is a specialized programming language used within AutoCAD to automate tasks and enhance functionality. This dialect of Lisp is tailored for AutoCAD and its various versions, allowing users to streamline operations, customize tools, and create specialized applications.

Step-by-Step Guide to Loading LISP in AutoCAD 2025

1. Initiate the Loading Process:
   Launch AutoCAD and either type the command APPLOAD in the command line or navigate to the menu. You can do this by selecting Tools from the main menu, then choosing Load Application.

2. Access the Load Application Dialog:
   After invoking the command, a dialog box named "Load Application" will appear. This is where you can manage LISP files.

3. Locate and Add LISP Files:
   In the dialog box, click on the Add File button. This action opens a file browser window. Navigate through your file system to find the LISP file you wish to load.

4. Select the LISP File:
   Once you locate the desired .lsp file, select it and click the Open button. The file will now appear in the list within the Load Application dialog box.

5. Confirm the Loading:
   Make sure that the file is listed in the application load window. Click on the Load button to upload it into the current AutoCAD session.

6. Close the Dialog:
   After confirming that your LISP file is loaded, click Close to exit the Load Application dialog.

Adding LISP Files to the Startup Suite

For frequent usage, you might want to automatically load specific LISP routines each time AutoCAD starts. Here’s how to do it:

1. Open the APPLOAD Command:
   Enter the APPLOAD command again.

2. Access the Startup Suite:
   Within the Load Application dialog, look for the ‘Startup Suite’ section and click on the Contents button.

3. Add to Startup Suite:
   Click the Add button, navigate to your desired LISP file, select it, and hit Open. Repeat this for any additional LISP files you want to include.

4. Finalize Your Selection:
   Once all required LISP files are added to the Startup Suite, press Close to confirm your choices.

Locating AutoCAD LISP Files

To find existing LISP files associated with AutoCAD, check these common directories:

• Default Locations: LISP files are typically stored in installation directories, such as C:\Program Files\Autodesk\AutoCAD 2025\Support or similar paths depending on custom installations.

Learning and Developing in AutoLISP

If you’re interested in creating your own AutoLISP routines, resources such as "Practical Common Lisp" and "Successful Lisp" are invaluable for understanding and honing your skills in this programming language.

FAQ

1. Can I use AutoLISP with AutoCAD LT?
No, AutoCAD LT does not support AutoLISP or the APPLOAD command, limiting automation capabilities in this version.

2. What file formats do LISP routines typically use?
LISP source files generally use the .lsp extension, while compiled files utilize a .fas extension for better performance.

3. How can I verify if a LISP file loaded successfully in AutoCAD?
You can check by running commands defined in the LISP or looking for output messages in the command line to confirm that the file functions as expected.