How to Create Lisp File in AutoCAD?

Understanding LISP Files in AutoCAD

LISP files are versatile ASCII files used within AutoCAD that can be customized and edited using any text editor. These files serve as a foundation for developing automated routines, enhancing the functionality of AutoCAD. Unlike regular drawing data, a LISP file is a template that can be adapted for personal use or for specific tasks within the AutoCAD environment.

Creating a New LISP File

1. Choose a Text Editor: Open a text editor of your choice, such as Notepad or any code editor that supports plain text.

2. Write Your Code: Begin coding your LISP functions. For example, a simple LISP function could look like this:
   lisp
   (defun c:HelloWorld ()
   (princ "Hello, AutoCAD World!")
   )

3. Save the File: Once you have written the code, save the file with a .lsp extension. Choose a memorable location on your computer, such as C:\LISP Files\myfile.lsp.

Loading a LISP File into AutoCAD

1. Open AutoCAD: Launch your AutoCAD 2025 application.

2. Access the Load Application Command: Click on the “Manage” tab located in the AutoCAD ribbon.

3. Select Load Application: In the “Applications” panel, find and click on the “Load Application” option.

4. Locate Your LISP File: In the dialog that appears, click on “Browse” and navigate to the location where your .lsp file is saved. Select the file.

5. Load the File: Once the file is selected, press the “Load” button. Your LISP file is now available for use within AutoCAD.

Executing LISP Functions

1. Open the Command Prompt: After loading your LISP file, go to the AutoCAD command prompt at the bottom of the screen.

2. Call the Function: Type the name of the function you want to execute in parentheses, for instance:
   lisp
   (HelloWorld)

   Then press “Enter.” The function will execute and display any relevant output.

Making LISP Files Access Permanent

For those who wish to have their LISP files available every time AutoCAD starts, follow these steps:

1. Access AppLoad Command: Run the command APPLOAD in AutoCAD.

2. Open Startup Suite: In the dialog box, click on the “Startup Suite” and then hit the “Contents” button.

3. Add Your File: Click the “Add” button to locate and select your .lsp file as previously described.

4. Finalize the Setup: After adding the appropriate LISP routines, click on the “Close” button to save your changes.

Editing Existing LISP Files

1. Start the Visual LISP Editor: Open AutoCAD and go to the Tools menu. Select “AutoLISP” and then “Visual LISP Editor,” or simply type VLIDE in the command prompt.

2. Open Your LISP File: Use the “File” menu in the Visual LISP Editor to open the relevant .lsp file you want to modify.

3. Make Changes: Edit the code as needed.

4. Save Your Changes: Ensure to save your work before closing the editor.

Frequently Asked Questions

Q1: Can I use LISP files on AutoCAD LT?
No, AutoCAD LT does not support AutoLISP functionalities, and the APPLOAD command is not available for this version.

Q2: Where are LISP files typically stored in AutoCAD?
LISP files can be stored in designated support file paths set in AutoCAD options under “Files.” Common locations include the AutoCAD installation directory or user-defined folders.

Q3: How can I learn more about AutoLISP programming?
Numerous resources are available online, including tutorials, forums, and specialized courses focused on AutoLISP programming for AutoCAD. Consider interactive platforms or video tutorials for hands-on learning.