dcpu16 0.4.0

DCPU-16 assembler, disassembler and emulator
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DCPU-16 assembler, disassembler and emulator written in Rust.

DCPU-16 is a CPU specification from the never-completed game 0x10c by Notch (from 2012). More info about the DCPU-16:

To run DCPU-16 programs with hardware devices (such as a monitor, keyboard, etc.), use:

Completed features

The DCPU-16 is feature complete and ready for use:

  • Assembler
    • Labels
    • String literals
    • Arithmetic literals (e.g. SET A, 0x8000+100*3)
    • Readable error messages
  • Disassembler
    • Separate tokenizer
    • Colorized output
  • Emulator
    • All DCPU-16 v1.7 instructions are supported
    • A few extra instructions, good for debugging and testing
    • Devices
      • Monitor (LEM1802)
      • Keyboard
      • Floppy drive (M35FD)

Planned extended features

  • More unit tests
  • Concurrency support
  • Communication between DCPU-16 computers
  • A simple programming language that compiles to DCPU-16


Run cargo build --release and add dcpu16/target/release to your PATH:

  • assembler
    • $ dcpu16-assembler program.asm -o program.bin
  • disassembler
    • $ dcpu16-disassembler program.bin
  • tokenizer
    • $ dcpu16-tokenizer program.bin
  • emulator
    • $ dcpu16 -p program.bin


Apart from providing binaries, this crate can also be used as a library and embedded into other programs. An example of this can be seen in dcpu16-gui.


Some extensions (possibly temporary):

--- Special opcodes: (5 bits) --------------------------------------------------
 0 | 0x13 | OUT a | prints a null-terminated string located at a in memory
 0 | 0x14 | OUV a | prints a value in decimal and then a newline

Since hardware is not supported, you can use OUT to print to regular standard output. Another temporary behavior is that the CPU is terminated if it reads a 0x00 instruction.

Extensions to the assembler:

-- Assembler instructions ------------------------------------------------------
 DAF c, v     | DATA FILL - repeats a value a certain number of times
              | c (count) and v (value) must be numerical literals
              | e.g. DAF 256, 0xffff  ; Fill 256 words with -1


Save the following as prog.asm:

            OUT hello                   ; Print the string defined at 'hello'
            DAT 0                       ; This will terminate the program    

:hello      DAT "Hello World!\n", 0

Assemble the program:

$ assembler prog.asm -o prog.bin

Run it:

$ emulator prog.bin
Hello World!