Author Topic: SEGA CD: "Snatcher" Bug while running MD 3in1  (Read 4661 times)

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Offline Fab

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SEGA CD: "Snatcher" Bug while running MD 3in1
« on: June 28, 2013, 11:10:22 PM »
Help when I try to play snatcher using a SEGA CD Bios File i can't get any texts and the image color of the chara pictures are displayed wring check the pictures

upper pic: using original sega cd 2 bios without flashcard
downer pic: using md3in1 flashcard booting multiple patched SCD 2 Bios




anyone has the same?!

Offline ChillyWilly

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Re: SEGA CD: "Snatcher" Bug while running MD 3in1
« Reply #1 on: June 30, 2013, 07:12:13 AM »
Why are you trying to use a patched BIOS to run a game that works without the patch? Patched BIOSes are for running games from other regions, not the same region. For example, if you want to run a Japanese CD, you load the patched Japanese BIOS to boot the CD.

Offline Fab

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Re: SEGA CD: "Snatcher" Bug while running MD 3in1
« Reply #2 on: June 30, 2013, 11:22:35 AM »
my Setup:

Japanese Model 1 Mega drive with a 50hz/60hz switch
PAL Sega CD Model 2

Snatcher PAL runs perfect without the flashcart
Snatcher NTSC US doesn't run correct even with a original unmodified NTSC-U SCD 2 Bios or a patched regionfree bios?! Which Bios I have do use?

Offline ChillyWilly

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Re: SEGA CD: "Snatcher" Bug while running MD 3in1
« Reply #3 on: June 30, 2013, 12:03:22 PM »
Well, that's a strange setup. I would think you would need the patched US BIOS to boot the US NTSC CD, with the switch in 60Hz mode. However, I'm not sure if the game is reacting to the Japanese setting or not. You would also need a region switch in addition to the 50/60Hz switch to check that out. The PAL game probably works because they never expected someone to try running a PAL game on a Japanese console.

The CD provides one level of region handling: The BIOS is hardcoded for US, Japan, or Europe. The console provides two more levels of region handling: There is a setting for Domestic (inside Japan), or Foreign (outside Japan), and NTSC (60Hz), or PAL (50Hz). CDs only boot when the region of the CD matches the region data in the CD BIOS, but once a game is booted, it can then check the console region bits or not depending on whether they meant for a game to be restricted or not.

So what I'm saying is it's possible the NTSC US CD is booting, but then see the console is Japanese and is trying to show Japanese text... which it doesn't have since it's a US disc.
« Last Edit: June 30, 2013, 12:06:22 PM by ChillyWilly »

Offline Fab

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Re: SEGA CD: "Snatcher" Bug while running MD 3in1
« Reply #4 on: June 30, 2013, 02:51:46 PM »
that makes sense to me but why is the PAL game also bugging while loading a PAL SCD File via flashcard and whithout the flashcard its playing perfect with booting up in 50hz mode?

Offline ChillyWilly

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Re: SEGA CD: "Snatcher" Bug while running MD 3in1
« Reply #5 on: June 30, 2013, 10:08:00 PM »
No idea - I don't know what is different about the patched CD BIOSes since I didn't work on them.