FCEUX 2.2.2 VRC6 mapper "bug"

Discuss emulation of the Nintendo Entertainment System and Famicom.

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Broke Studio
Formerly glutock
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FCEUX 2.2.2 VRC6 mapper "bug"

Post by Broke Studio »

Hi,

FCEUX is not letting me use SRAM with mapper 24, but only with mapper 26.

Looking at the source, I found those lines in vrc6.cpp :

Code: Select all

	if (is26)
		setprg8r(0x10, 0x6000, 0);
obviously, this is the problem (for me, since my Everdrive let me use SRAM with both mappers).

Can someone tell me exactly what tools I need to recompile FCEUX ? ( without "if (is26)" )

Or is there someone kind enough to recompile it with the modification and send me the .exe file ?


edit : I found a workaround, loading a ROM using SRAM (which initialize SRAM in FCEUX) and then loading my ROM with mapper 24. But I'm still interested in the tools needed, or the modified exe file.
My first game : Twin Dragons available at Broke Studio.
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rainwarrior
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Re: FCEUX 2.2.2 VRC6 mapper "bug"

Post by rainwarrior »

glutock wrote:Can someone tell me exactly what tools I need to recompile FCEUX ?
All you need is the source code, and a free version of Visual Studio. Older free versions were called "Visual Studio Express" but I guess it's now "Visual Studio Community"? (Should work with older versions of VS Express just fine, too.) https://www.visualstudio.com/

If you want bleeding edge source code, instead of the last archived version, you can use SVN to get the latest code from FCEUX's sourceforge server: https://tortoisesvn.net/ / https://sourceforge.net/p/fceultra/

If this is a bug, you can report it at FCEUX's sourceforge bug tracker, by the way: https://sourceforge.net/p/fceultra/bugs/
lidnariq
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Re: FCEUX 2.2.2 VRC6 mapper "bug"

Post by lidnariq »

When that line was added in rev2810, it looks like cah4e3 went to special effort to differentiate between mapper 24 and mapper 26 behavior.

I'm not clear whether that was intentionally avoiding breaking some assumption in Akumajou Densetsu or just being cautious.
tepples
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Re: FCEUX 2.2.2 VRC6 mapper "bug"

Post by tepples »

And in any case, it ought to be changed to allow games to override the PRG RAM size if the NES 2.0 header is present.
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Broke Studio
Formerly glutock
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Re: FCEUX 2.2.2 VRC6 mapper "bug"

Post by Broke Studio »

rainwarrior wrote:
All you need is the source code, and a free version of Visual Studio. Older free versions were called "Visual Studio Express" but I guess it's now "Visual Studio Community"? (Should work with older versions of VS Express just fine, too.) https://www.visualstudio.com/
Thanks, I'll definitly try this. I used Visual Studio Express years ago and wasn't aware of the new version (Community).
My first game : Twin Dragons available at Broke Studio.
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