[SOLVED] 2 files with floppy image

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JAAman
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Re: 2 files with floppy image

Post by JAAman »

m12 wrote:
JAAman wrote:therefore, any driver which perform this check, would be incompatible with any disk formatted with any version of windows or DOS other than win98 (and incompatible with disks formatted with some copies of win98 as well)
So does this mean we need to cause more compatibility issues by setting it randomly?
setting it to "MSWIN4.1" IS setting it randomly

Windows alone uses more than 3000 different strings depending on which version you are using and who installed it, and another 6000 different string for various versions of DOS
other non-MS OSes should also use their own individual strings

basically, any user who uses an OS which even looks at this string, already doesn't expect it to work with your disk anyway (since that would be a hobby OSdever) and is clearly violating the specification (in fact, there have been so many violations of the specification, that MS changed the specifications for better compatibility with the incompatible drivers) -- there is no excuse for this, the only reason anyone would look at that field is to support non-standard implementations -- which would be incompatible with the standard anyway, and thus pointless to "remain compatible", and if what it is checking for is specifically the string "MSWIN4.1" then it will only be able to read disks that were formatted with plain, non-customized versions of win98 FULL retail (of which only a few copies were ever sold)


the correct way to handle this field is to set it to your own name for instance, disks formatted with JaaOS is set to "JOS" plus version number
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neon
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Re: 2 files with floppy image

Post by neon »

Hello,
JAAman wrote:
neon wrote: 1. Use bpbOEM db "MSWIN4.1". Not doing so may cause some compatibility issues with some systems.
this is only true if you are running some small 3rd party OS which uses a FAT driver which clearly ignores the FAT specification (no MS FAT driver has ever been released to the public which does this check)
I agree with this one. To be fair, according to the whitepaper "MSWIN4.1" is a recommended setting to avoid compatibility errors with some FAT drivers that do erroneously rely on the field on Microsoft operating systems. The document is relatively old however and so may not be entirely reliable today. Nonetheless for hobby operating systems it really shouldn't matter.
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