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Retro Roundup: Old Computers Emulated Right In Your Browser
An anonymous reader writes: If you ever wanted to program an Altair, an Apple I, or a COSMAC ELF you may think you either have to buy one (expensive now) or load and configure simulation software. However, there's a slew of browser-based emulators for everything from a PDP-11 to Windows 1.0 out there. Some use Java, but many use Javascript and many perform better on a modern PC then they did in their original. If you want to learn some history or just want to finally play with the computers you saw in the magazines 35 years ago, these are great fun and slightly addictive.
Also, people who apparently either don't have any sense of fun, or perhaps they're all millennials and poo-poo anything older than they are, or maybe both. For cryin' out loud, people, these emulators for (in some cases literally) antique hardware aren't intended for 'serious' use, or development, or anything like that: They're intended to be fun to play with, or maybe educational since most of them are emulating systems that either don't exist anymore or are so rare that you'll likely never even see one in the flesh. Yes, some of us are old enough that we actually owned (or built, as the case may be) some of these systems, but again: If you're complaining about them then I question whether you have any sense of what's fun or not. When some of these computers were available, screwing around with computers was still fun; they're not as much fun in many ways now, because it's all too much serious business, and too much of it is closed-source, proprietary, locks the user out, physically inaccessible, or in some extreme cases you get prosecuted or sued in civil court for getting caught messing with it. In many cases some of the hardware may as well be potted in a solid brick of opaque epoxy, for all the good it'll do you to try to get at the actual hardware. Building a complete computer system from component parts (i.e. requiring soldering)? So impractical now as to be nigh-unto impossible (I could do it, but there's no point anymore). The closest thing we have anymore is you younger guys screwing around with microcontrollers (many of which are more powerful than many of the computers being emulated here, ironically enough), but even then you have to have an entire modern computer just to write the simplest code for them, there's no 'front panel' where you can enter machine code directly, one byte at a time. Don't knock it 'till you try it, guys (and ladies).
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
My native FLEX / 6809 machine emulator (for Windows XP and at least several Windows versions on up... don't use Windows any more, so I dunno. :)
Late-70s / early-80's machine era.
Front panel, graphics card, single stepping, lots of software including assemblers and compilers. Stable.
If you ever used 6809 Flex, you'll be right at home. Otherwise, probably don't bother.
I've fallen off your lawn, and I can't get up.
The problem, as I see it, is that by doing it in Javascript, we're introducing a new dependency: the code will only work on a browser produced in 2015.
Well you can rest easy then, because no one is writing this stuff in JavaScript.
What triggered this change is Emscripten, which is a back end for LLVM that targets ... JavaScript. Actually it targets asm.js, which runs at about 1/2 native speed in Firefox (not so fast in Chrome, because Google thinks the solution to the same problem is NaCl).
What that means is any compiler that uses LLVM can now compile to asm.js. Which means any program written in Python, Rust, Go (there are a whole pile of languages) can now be compiled to run in the browser. In particular Clang is a C compiler for LLVM. Dosbox is a x86 + MSDOS emulator, written in C. Ergo Dosbox can now be compiled to JavaScript and this run in the browser. Js-dos is a site apparently dedicated hosting games that does just that. The game console emulators are also written in C. So they to can and now have been compiled to asm.js. Because modern web browsers support WebGL, OpenGL games that have been open sourced (like Quake3) have also been compiled to JavaScript, and run spookelly well. Which is how we get to the plethora of games mentioned in the article. Pity it didn't mention the technology behind it.
But why stop a games? Sqlite3 has been recompiled for Javascript. It can do in browser SQL queries in about 2ms, and is a damned site nicer to use than wandering through a spiderweb of Javascript objects. But why stick to something sane? You can now do ffmpeg encoding in your browser.