The Null Device

This is pretty awesome: a browser-based SNES NES emulator written entirely in JavaScript. Let me repeat that: someone wrote code in JavaScript (not in Flash or Java or anything faster) for emulating a Super Nintendo almost in its entirety*, from the 6502 CPU to the graphics and I/O hardware, and got away with it (it gets a respectable 33 frames per second in Chromium, though crawls along painfully in Firefox). The source code is all there in the page, unobfuscated, and the author has released the code (which is fairly elegantly laid out and comprehensible) under the GPL. Which means that it's probably only a matter of time until someone uses it to build a DHTML-based Commodore 64 or something.

* there's no sound, as one might expect.

(via Download Squad) ¶ 6502 awesome emulation javascript nes nintendo retrocomputing tech 2

Someone has written a JavaScript-based 6502 assembler and emulator. The system compiles 6502 assembly language into JavaScript, includes a (low-resolution) emulated video display, and is powerful enough to play simple games like Pong (included in the examples).

In other 6502-related news, here is a commented disassembly and detailed analysis of Rob Hubbard's music playing code, as seen in numerous Commodore 64 games of the 1980s (and later ripped off by crackers and demo scenesters). If there was a museum of feats of 8-bit computing, this routine would be sitting in a prominently placed glass case in one of its wings.

(via jwz, c64music) ¶ 6502 8-bit assembly language c64 chiptunes emulation hack value javascript music retrocomputing tech 2