The uBASIC Debugger (often utilized via PC-based IDEs like UBDebug) is a troubleshooting framework used to write, test, and fix automated uBASIC scripts for the Canon Hacker Development Kit (CHDK). It provides developers with tools to catch errors before loading scripts onto a Canon PowerShot camera. 🛠️ Core Debugging Features
When writing scripts for CHDK’s tiny uBASIC interpreter, standard programming bugs can easily freeze the execution. The built-in and external debugger tools provide several layers of defense:
On-Screen Error Tracking: If a script crashes on the camera, CHDK prints a uBASIC:nn err code in bright red text in the top-left corner of the display. The nn tells you the exact line number where the interpreter failed.
File Logging: By using the print_screen command in your code, you can force the camera to log console outputs directly to a text file inside the /CHDK/LOGS/ directory.
UBDebug IDE: Since debugging on a tiny camera screen is difficult, developers use UBDebug, a specialized Integrated Development Environment (IDE) for Windows/Linux. It allows you to simulate script behavior, catch loop nesting violations (uBASIC limits you to 4 nested for loops and 10 nested gosub calls), and verify syntax errors on your computer. 🚀 Getting Started Step-by-Step 1. Set Up Your Environment
Do not write raw code blindly. Download a dedicated text editor or the UBDebug IDE. Ensure all your uBASIC files use the strictly required .bas file extension (Lua files use .lua). 2. Implement the Logging Hook
To trace variables as your script runs on the camera, include the print_screen statement at the very top of your script: print_screen 1 Use code with caution.
Passing a positive integer creates a clean log file named LOG_0001.TXT on your SD card, which overwrites previous errors and tracks your variables sequentially. 3. Watch the 10ms Parsing Tax
Unlike standard languages, the uBASIC interpreter is incredibly lightweight and takes roughly 10ms to process every single line of code—including rem (remark/comment) statements and blank lines. If your script is lagging or throwing timed-out errors, the debugger’s primary optimization strategy is to delete excessive comments and compress your code structure. 4. Execution and Testing