svm

README

SVM

note: This project is strictly for personal educational purposes. Don't expect it to be of any practical use.

SVM implements a programmable virtual machine for a fictional 16-bit architecture. It comes with an assembler and the runtime. The runtime contains the CPU and a number of virtual hardware peripherals which one can interact with through a program. These include, among other things, a sprite-based display and a gamepad.

Refer to the documentation in the docs directory for details on the assembly language, the architecture and how to interact with peripherals.

Directory Overview

• arch: A small, shared package which defines the CPU architecture. Including the instruction set and registers.
• asm: Implements the assembler.
  • asm/ar: Implements the compiled binary file format. Archives are what the assembler produces.
  • asm/eval: A helper package for the assembler. It evaluates compile-time expressions.
  • asm/parser: The tokenizer and AST builder for the asembler. It reads SVM source files and parses them into an Abstract Syntax Tree.
  • asm/syntax: A helper package for the assembler. It examines a newly parsed AST and ensures it does not contain syntax errors. Additionally performs translations of certain code constructs.
• cmd: Contains executables. These are assembler/VM front-ends and some useful tools.
  • cmd/svm: Contains the executable VM. This is the one that actually runs your programs.
  • cmd/svm-asm: Contains the executable front-end for the assembler.
  • cmd/svm-fdd: A small program which creates 1.44MB floppy disk images. These are what the VM uses to load your programs.
  • cmd/svm-sprite: A small tool which generates SVM source code from sprite sheets.
• devices: The root directory for implementations of all the virtual hardware components. As well as defining some common shared interface types.
  • devices/fffe/clock: Implements a simple clock and timer device.
  • devices/fffe/cpu: Implements the CPU that runs the code.
  • devices/fffe/fd35: Implements a virtual 1.44MB floppy disk drive.
  • devices/fffe/gp14: Implements a virtual gamepad. It exposes a real gamepad to VM code.
  • devices/fffe/sprdi: Implements a virtual display. It allows a program to render sprites.
• docs: Contains text files with documentation for various components.
• testdata: Contains sample SVM source code and some other testing things.

TODO

• Add audio support.
  • Create a specification for a audio hardware.
  • Create a device implementation of the specification.
  • Create test code to illustrate use of the device.
• Add network support?
  • Create a specification for a network adapter.
  • Create a device implementation of the specification.
  • Create test code to illustrate use of the device.

License

Unless otherwise stated, this project and its contents are provided under a 3-Clause BSD license. Refer to the LICENSE file for its contents.