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1. Select a sample program or write your own using the Custom preset


2. Once the Jack code is ready, click Compile to compile to bytecode


3. The bytecode can be edited freely. When you are ready to run the program, click load program to initialize the runtime. This will initialize the memory and prepare to execute the bytecode instructions.


4. When the program is loaded it can either be stepped through instruction by instruction using the Step button, or Run. Stepping will update the memory display at each step, while running will only update the memory when the program is paused.

Note: Loading a new preset will clear any edits. Copy and paste the code to save it locally if you want to retain any changes.