Ardufuck

An interactive Brainfuck interpreter for Arduboy

• Enable single character input for the , instruction
• Spruce up the UI a bit
• Reset more of the VM between runs (i.e. clear input/output)
• An in-game debugging mode would be cool
• Allow the debugger to import/execute arbitrary BF programs or lua libs

The sketch starts in the "Edit - Move" mode. You can tell which mode you're in by the color of the LED:

Here's a description of the controls in each mode:

This mode is for navigating and reading the program. You can navigate the program as if it was a grid, moving up and down wrapped lines.

• D-Pad L/R/U/D -- Move the cursor around the program
• A -- Enter mode "Edit - Editing"
• B + Down -- Enter mode "Run - Paused"

This mode is for editing the program. You can move by single characters back and forth, and cycle through the set of Brainfuck instructions under the cursor

• D-Pad L/R -- Move the cursor back and forth
• D-Pad U/D -- Cycle through Brainfuck instructions at current character
• A -- Exit mode "Edit - Editing"
• B + Down -- Enter mode "Run - Paused"

This is a standby mode before running the program

• A -- Run program
• B + Up -- Enter mode "Edit - Move"

In this mode the Brainfuck VM executes one instruction per frame.

• A -- Pause program
• B + Up -- Enter mode "Edit - Move"
• Hold D-Pad R -- Enter mode "Run - Fast Forward"

In this mode the brainfuck VM executes 8 instructions per frame.

• Release D-Pad R -- Exit mode "Run - Fast Forward"

The program has completed running

• A -- Return to mode "Run - Paused", rewinding the VM

1. You'll need to install

• The Arduino IDE
• CMake
• A C++11 compatible compiler

1. In the Arduino IDE:

• Install the library Arduboy2 @ 6.0.0
• Open the git directory as a sketch
• Set up the target board as Arduino Leonardo

This project includes a nice little debugger written in lua.

To build the debugger:

1. cd debugger
2. cmake -S . -B build
3. cd build
4. make

The debugger executes by default a file in the same directory called debugger.lua. Just run ./debugger

To change the program that is initially loaded you can adjust the program local.

The debugger has a simple text-based interface

Code:
++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>++.
^                                                                                                         
Data:
000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 
 ^                                                                              
Done: false
Input:  Output: 
n(ext) | b(reak) X | d(elete) X| i(nput) | q(uit) | f(orward) | (b)a(ck) | e(xec)
> 

You can see that we display the current program, and a cursor to mark where execution currently is, as well as a view into the surrounding data cells, and some state of the VM.

the instructions you can give at the prompt:

• n/next -- Execute the next instruction
• b X/break X -- set a breakpoint for the given instruction, e.g. b . will break on each instance of .
• d X/delete X -- delete the breakopint set for the given instruction
• i/input -- Prompt for input, will only take the first character
• q/quit -- Quit the debugger
• f/forward -- Move the cursor forward an instruction without executing it
• a/back -- Move the cursor backward an instruction without executing it
• e/exec -- Execute the program until it finishes or we hit a breakpoint