Welcome to this VSP directory.

"VSP" means "Very Simple Processor" (officially) and designates a 32-bit microcontroller that I have imagined, in parallel (and sometimes in contradiction) with the F-CPU project. My first goal is to design something so simple that I can develop it alone, with very little means and efforts. This forces me to make some curious and counter-intuitive decisions so "VSP" might be "Virtual Stupid Past-time" as well.

My other goal is to enable anybody, not just VHDL and CPU architecture gurus, but also computer hobbyists or even students, to understand, use and even participate in this project. So this package is not just a simulator, an assembler, a disassembler, a manual, a development tool, it is all that and more ! Every part is integrated in the others (and vice versa), so the whole is coherent, easy to use and quick to develop (and to maintain, despite but thanks to the messy programming that JavaScript enables).

The only requirement is that Firefox (or any other Gecko-based browser) is installed on your computer : this integrated, all-in-one project heavily relies on Mozilla's JavaScript engine. Supporting other browser's JS engines would make development uselessly painful. Remember that the VSP's philosophy is to make everything so dumb simple (often by choosing unusual methods) that we can concentrate on the real issues of CPU development.

Happy clicking !

Description, documentation and references (/doc directory)

• The general introduction to the VSP : the must-read. (ok)
• The assembly langage manual. (almost complete)
• The original text-only draft. Several aspects are outdated so please refer to the above first link in priority.
• The interactive opcode map of the VSP. (ok)
  You can reach a specific opcode from another page, for example : SHH.
  Some statistics are also generated on the fly (aliases, form usage and flag usage)
• The Interactive Assembler is a simple form that lets you assemble single instructions. It's very handy for testing.
  It is now exported to other windows, like this : add d0 d1 and it also provides disassembly of single opcodes : A8E2F5EBh (ok)

The pages of the Instruction Set Manual of the VSP (/ISM directory)

They can be accessed from anywhere, for example by clicking on the corresponding name in the interactive opcode map or in the floating assembler window. (ok but missing examples)

Various early clickodromes, prototypes and sandboxes (/test directory)

• The Opcode autotest is now available. This page exercises the disassembler with the assembler's output, seeking inconsistencies. (ok)
• The Execution Units can be explored manually. (bork)
• The old pipeline simulator is still available, but incomplete and useless (but funny and not lethal).
• Some basic testbenches for the associative arrays in Javascript, text to int conversion and FIFO algorithm (reused in several places).
• A method to draw arbitrary segments, for a later use in GNL (a graph-based programming tool) and its editor (ploped is a first renderer prototype). (incomplete)
• Advanced JavaScript (use this at your own risks !) for loading data from a file and saving arbitrary data to a file. (bork)

Others

• The /JScore directory contains JavaScript files for the VSP's core, like all the assembly, definitions and small utilities to make the simulator tick, without communication with any user interface.
• The /JSgui directory contains JavaScript files for the Graphical User Interface in order to keep it separated from the real core files.
• The issues.txt lists some known issues and some rationales...
• The updates.txt keeps the track of the major changes applied to the files.

Download

• The whole directory tree packed together for your offline pleasure.

Notes :

• Please keep in mind that this work is constantly in progress, the files change often and bugs appear and disappear without prior notice.
• Check the updates.txt file for the latest changes, known bugs and missing features.
• All these files are (C) Yann Guidon 2002-2007 and are only provided for the visitor's fun.
• These pages are barely W3C-compliant, I just want them to work under Firefox. I'm an electronician, not a web designer !
• Thanks to all people who have helped (directly or indirectly) with code, comments and insight