| Introduction
& History
On October 15th 2000, Jeffrey Quinn
released version 0.22a (aka "Borg")
of his emulator WinAGES.
As it is the first emulator which allows you to play Sega CD games, it is a milestone
in the history of Sega emulation. More than four years lie between the release
of the first Genesis emulator (GenEm in 1996) and the release of WinAGES Borg
- a nice proof of the fact that it is very difficult to emulate this system.
The current version (0.25a)
is more compatible than the initial release, and most of all a lot faster
(though still rather slow, especially on non-Intel CPUs).
If you are interested in the history of the Sega CD
console, I suggest you check out
Sam Pettus' background report called "A
Console Too Soon", which can be found at SegaBase (see link on the right
navigation bar).

What does WinAGES Borg
emulate?
The
Sega CD not only adds a CD drive to the Genesis, it also improves it with another CPU, a
graphics chip for scaling&rotating images and a PCM sound chip. The
current version of WinAGES emulates the graphics chip partially (not all
effects are emulated correctly), but does not emulate the sound chip. However,
CD audio tracks are played. Many games which use one of
those components extensively (for example Thunderstrike, Soul
Star, Lunar 2...) do not
work yet. The "basic"
system design (inter-CPU communication, CD drive) is emulated however. Jeff
did not use HLE (High-Level Emulation) for the BIOS - he managed to emulate
the CDC/CDD (low level CD drive access functions) directly, which means that
overall emulation will be a lot more compatible in future revisions of the
emulator.
"In future revisions?", you ask. As a
matter of fact, only a few games are actually playable with the current
version of the emulator (see compatibility list below, still referring to
0.24a though). Many games show something,
e.g. the intro, some full-motion videos... But most of them crash at a
certain point because they use some yet unemulated features of the Sega CD system.

Necessary files
If you want to play Sega CD
games using WinAGES, you need the following files:
WinAGES 0.25a archive
ASPI.
This is a special interface for accessing the PC's CD drive.
It is available here.
Your system needs to be restarted after installing it.
The Sega CD BIOS files. They
are available here
The Genesis OS ROM,
available here
The 32X BIOS files, available
here
And of course: Sega CD games. WinAGES
supports the direct use of your PC's CD/DVD-ROM drives
to play "real" Sega
CDs as well as the use of
ISO images. I do not know any sites currently carrying ISO images. DO NOT
ASK ME, and DO NOT ASK FOR IT IN THE TAVERN.
Getting started
After you have downloaded all the necessary files above, unpack everything
into a newly created directory. Then start AGES.EXE. The first thing you need
to do is to specify all the System ROMs. Select "Config" - "File IO"
- "Load System ROM". If you have downloaded all files from the above
links, the file mapping for the system ROMs is as follows:
- Genesis = Genesis_OS_ROM.bin
- 32X Master SH2 = 32X_M_BIOS.BIN
- 32X Slave SH2 = 32X_S_BIOS.BIN
- 32X M68000 = 32X_
G_BIOS.BIN
Sega CD (U) = scd_110.bin
Sega CD (J) = mcd_101.bin
(not emulated yet, however!)
Sega CD (E) = mcd2_200.bin
Set "Config" - "Machine" - "Miscellaneous"
- "Region" to Auto
Detect. Activate Use
System ROMs for "Config"
- "Machine" - "Genesis" and "Config" - "Machine"
- "32X". Adjust the "Frame Skip" and "Screen Size"
settings in "Config" - "Graphics" according to your PC's
speed. If you intend to play "real" Sega CD games through the use of
your PC's CD/DVD-ROM drive, you need to select the Default
CD Drive in the "Config"
- "File IO" menu.
Now, WinAGES is set up to play Genesis, 32X and Sega
CD games.
Playing the games
You
can either play a game directly from CD, or you can play it from an ISO image.
To do the first, simply insert the Sega CD game CD into your default CD drive
and start AGES. All you need to do now is to select "File" -
"Boot Sega CD". If you want to play from an ISO image, select
"File" - "Load ROM" (don't forget to set the file type to
Sega CD) and specify the ISO image. Please not that many games do not work in
ISO format because they require the CD audio tracks.
Depending on the game's country, the well-known
American or European startup screen is shown - press start, and the game
starts loading. Please note that Japanese games can only be played using the
following trick: When
the Japanese BIOS title screen is display, press the Start button repeatedly
very fast. That way, a part of the BIOS code is skipped and the game might
load.
Final words
As I pointed out several times, the release of WinAGES Borg is a milestone for
the Sega emulation scene. Jeffrey Quinn has achieved something which has thought
to be almost impossible, because of the general complexity of the system and
especially because of the lack of technical documentation available for the
system. The release of WinAGES was a complete surprise. Kudos to him for that!
On the
other hand, WinAGES is far from being perfect in terms of Sega CD emulation. Let
me summarize its drawbacks: In its current state, only very few games are
playable, it has no sound support except CD audio.
But WinAGES has a lot of potential, as shown with the latest
release (0.25a), and I am certain that
Jeff will do everything to enhance it in the areas I mentioned. He has clearly shown
that Sega CD emulation is possible, and that usually means (quoting him): "Let
the competition begin!". Two other emulators have joined this competition
now already, and I'm pretty much certain that we will see some
other working Sega CD emulators as well.
For now, I wish everyone a lot of fun with WinAGES Borg. When you've finished
playing around with it, please join the Sega discussions in the Tavern, to give
the authors some feedback.
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