Aeon Emulator Blog

December 25, 2009

Merry Christmas

Filed under: Aeon, Fun & Games — Greg Divis @ 8:00 am

By 1990, the PC was becoming a viable platform for home gaming able to compete with the likes of Nintendo and Sega. To play to the PC’s strengths of a common mouse and keyboard input, some different genres of game took off in the PC market compared to the consoles, one such genre was the adventure game. Something of an evolution of the older text-parser adventure games, the point & click graphical adventure game was huge for several years. If you were into those games, one of the companies you paid attention to was Sierra On-Line. Now defunct, with most of their IP’s owned by EA, Sierra was a big deal. They made King’s Quest, Quest for Glory, Police Quest, Space Quest – and it seemed like they added a sequel to each of those series almost every year.

In the late 80’s and early 90’s, Sierra distributed electronic “Christmas cards.”  For some reason, I still have a copy of this one goofy Christmas cartoon they made using their SCI adventure game engine.

Title Screen

In The Seasoned Professional, an inept actor gets dressed up in all of the wrong holiday costumes, all the while being scolded by the director for screwing it up.

Groundhog Day No

I thought this was pretty funny when I was 9 years old or so – the kind of humor they were going for was definitely aimed at that younger age group, but looking at it again now the nostalgia is hard to beat on something like this.

Seasons Greetings

Hope everyone reading this has a happy new year. See you in 2010.


December 22, 2009

What’s next

Filed under: Aeon — Greg Divis @ 10:46 pm

I wanted to get a new version posted before the end of the year, but it’s looking like that isn’t going to happen. I’ve made significant progress with the x87 floating-point unit, and been able to get Duke Nukem 3D and a few other games at least somewhat working, but I’ve also broken compatibility with a few games that used to work. I figured it would be better just to keep working on it until I’m fairly sure I’ve got any new bugs I’ve introduced fixed.

Anyway, since it seems some people are actually attempting to use Aeon now, here’s a kind of road map for what I’d like to have ready at each “major” version, so you know what to expect:

  • 0.6
    • Protected mode complete enough to run most DOS games that don’t require SVGA
    • Functionally complete, but not necessarily exact, FPU emulation
  • 0.7
    • CD-ROM/MSCDEX emulation
    • Improve emulated DOS command prompt (more commands, multiple drives)
    • Simple batch file support
    • SVGA*
  • 0.8
    • SVGA*
    • Program usability, UI improvements
    • Performance improvements
  • 0.9
    • Improve performance
    • Improve compatibility
  • 1.0 – Stable

*SVGA is listed in two versions because I’m not sure exactly how much of this I’ll be doing. Unlike VGA, it was a while before there was any kind of an SVGA standard like VESA, so I need to do some more research and decide how best to approach this.

This is not an exhaustive list. For example, I haven’t listed additional features that will be needed to properly support some of these, like a user-interface for manual drive mounting to support removable media like CD’s. I’ve deliberately tried to get all of the actual hardware/software emulation that I want to have feature complete (but probably not bug-free) by 0.8, so I can work on improving the application UI and performance up until I’m ready to call it stable.

Everything up to 0.9 should be considered an unstable, experimental alpha. 0.9 will hopefully be beta quality, and 1.0 will be stable.

December 13, 2009

Aeon Version 0.52

Filed under: Aeon, New Version — Greg Divis @ 4:30 pm

This build includes fixes to things that were broken in 0.51, and also a few other general improvements:

  • Fixed crash on startup due to the icon (!) embedded in Aeon.exe on some systems
  • Fixed bug in file system redirection that could sometimes cause a crash with the change directory command (Master of Magic setup)
  • Fixed mouse coordinate input bug where clicks would sometimes not register at the right position
  • DMA controller improvements
  • Sound Blaster 16 DSP improvements, digitized sound should work a lot better
  • Changed default Sound Blaster IRQ to 7
  • Added some protected-mode-related instructions
  • Redesigned and streamlined operand decoder in preparation for FPU instructions

Download here.

December 12, 2009

Master of Magic

Filed under: Aeon, Fun & Games — Greg Divis @ 10:00 am

It’s been a while since I’ve posted about a specific game, and I’ve had this post written for quite a while so this seems like a good time for it. I’ve always been terrible at strategy games, but for some reason I’ve also always had a soft spot for them. The first turn-based strategy game I really got into was Master of Orion II – which came bundled with Master of Magic when I bought it back in 1996.

Title Screen

Master of Magic had a lot going for it – cool premise of conquering a randomly-generated fantasy realm, nice graphics, fairly intuitive control (for the time). The game also had its share of flaws – the AI opponents could show some odd behavior, and on a technical side, the game ran pretty slow. That being said, it’s still fun to play for a while, and I kind of like being able to mash that giant “Next Turn” button on my tablet PC.

Think I cheated a little?

Technically, the game is also pretty interesting. Despite its expansive, colorful look, it’s a regular 16-bit real-mode DOS program. It does, however, make extensive use of Expanded Memory, and so far it’s the only program I’ve run in Aeon that created multiple named expanded memory handles. If you aren’t familiar with expanded memory, basically a program would ask the memory manager for a handle, then allocate chunks of memory using that handle – the memory could then be mapped into real-mode conventional memory 16k at a time. Mainly for diagnostic purposes, a handle could be assigned a name. Master of Magic not only created a named handle, it created 22 of them.


You can tell from this that they kind of divided up what they were storing in expanded memory using different handles. I’m not sure what the deal is with the “YO MOMA” handle, but I at least got a chuckle out of that when I first saw it. I’m sure the programmers didn’t expect anyone to see that, but being a developer myself I have an appreciation for that kind of thing :)

If you’re looking to play Master of Magic, it works fine in Aeon and DOSBox (though in either case I recommend turning the sound effects off, or your tactical battles will take forever). If you’re looking for a sequel or a more modern version of this game, you’re mostly out of luck, at least until Elemental: War of Magic is released.

This is what I get for publishing an old post like this. The setup program for Master of Magic has been broken for a few versions, and I never noticed this since it wasn’t part of my normal testing. It should be working again in 0.52. For reference, here’s the settings I used to run the game:

Music: General Midi (port 330)
Sound: No sound

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