After I uploaded some samples in lsdj.gb I get this "error sing" everytime I load the rom into the bgb emulator.
It says "Rom checksum failed. a real gameboys wouldn't care".
So apperantly there's no real issue here, but what does it actually mean?
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Means that it's an error that doesn't matter. Get it for customs romz all teh tiem. Has to do with making changes in some places and not editing the header (think I'm right?) to represent that in the checksum
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Sweeeeeeden
The checksum is a value that is calculated from all the bytes in the ROM to ensure that the ROM has not been corrupted. If there are any changes in the ROM, the checksum changes (unless you're extremely unlucky) and a verification process can detect this. Nintendo used this back in the day when people submitted Gameboy games on floppy disks to make sure the ROMs were not corrupted. If you care about this value being correct, you can use the RGBFix tool from the RGBDS assembler package.
You can also do this in BGB. Press esc to bring up the debugger window. Select file, fix checksums then file, save as and select where you want to save the file.
Last edited by nitro2k01 (Nov 19, 2013 7:15 pm)
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Sweeeeeeden
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西安
nitro2k01 wrote:
(unless you're extremely unlucky)
can you explain, nitro? this made me curious.
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Sweeeeeeden
The checksum value is just two bytes, or 16 bits big, so it can take on any value between 0 and 65535 (or in hexadecimal 0-FFFF). Since this is far less than the many thousands of bits that a typical ROM contains, there must be many (out of all completely random combinations) of ROM contents that give the same checksum.
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Orange County,CA /Las Vegas NV
this happens when you try loading the sav and gb. file at once. name the two files like whoa.sav and whoa.gb make sure of that, so your pc or emulator isnt loading 776312246 other "lsdj.sav files. and oh after you load just the rom,the sav will load with it, make sure the names match, good luck!
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Orange County,CA /Las Vegas NV
nitro2k01 wrote:
The checksum is a value that is calculated from all the bytes in the ROM to ensure that the ROM has not been corrupted. If there are any changes in the ROM, the checksum changes (unless you're extremely unlucky) and a verification process can detect this. Nintendo used this back in the day when people submitted Gameboy games on floppy disks to make sure the ROMs were not corrupted. If you care about this value being correct, you can use the RGBFix tool from the RGBDS assembler package.
na he's okay. he didnt load the rom by itself orrrr has too many sav files on his desktop with lsdj.sav soooo his bgb tried loading too many
savs
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Sweeeeeeden
Cuddle Television: What the hell are you talking about?
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remember that time nitro was wrongly wronged?
also remember that time..... you can't have 2 files with the same name and extension in same directory.
cuddle tv, pls.
Last edited by 12ianma (Apr 11, 2013 3:47 pm)
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Google RGBDS, it's a development kit for Windows, I use for homebrew programming. One of the files you get is called rgbfix.exe. Just put it in the same directory as lsdj, navigate there in a command prompt, and type
rgbfix -v lsdj.gb
It'll validate the checksums and your ROM will boot no problem.
Last edited by dawsx (Apr 12, 2013 12:22 am)
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I just have to click "OK" on the error message, there are no real problems. I was just curious what it meant.
If I might get into trouble with it, I'll remember you're tip, thanks.
But at the moment it seems more work than jut tapping enter when I open LSDJ 
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Orange County,CA /Las Vegas NV
pardon me I was stoned the fuck out, I read this again and realized what I said 
Sorry for the inconvience, anyhoot when I load samples I get that checksum shit it still works doe, dont worry 
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UK, Leicester
Cuddle Television wrote:
pardon me I was stoned the fuck out, I read this again and realized what I said
With posts like that, who'd have thought it?