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 Post subject: Help with getting files from a floppy-emulated ISO [solved]
PostPosted: Sat Jan 12, 2019 9:11 pm 
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I have a question that I cannot find answers to anywhere, so hopefully this might be a good place to ask for help. And yes, I have look over the wiki, but I didn't find an answer to my question. I could have missed it, though, but I don't think so.

How do you read and get information from a CD/DVD, when you set the image to be floppy-disk emulated? Does the floppy-disk image use a FAT12 filesystem on the floppy-disk image and then use code to load files from the CD/DVD? Or do you just ignore FAT12 all together and just use code to load parts of the CD/DVD/ISO? or what?

I was reading a Wikipedia page on 'El Torrito', (https://en.wikipedia.org/wiki/El_Torito_(CD-ROM_standard)) and it said that when in floppy-emulation mode, it acts as a virtual floppy-disk, but then it said before that when in hard-disk emulation mode, it get information directory from the CD/DVD. So is it only for hard-disk emulation, or is the same for both, but it is just say, or is there is mechanism to get information from the CD/DVD/ISO using a floppy-disk? Or do I just not understand something here


Last edited by saltlamp on Sun Jan 13, 2019 7:38 pm, edited 1 time in total.

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 Post subject: Re: Help with getting files from a floppy-emulated CD/DVD/IS
PostPosted: Sun Jan 13, 2019 1:59 am 
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saltlamp wrote:
How do you read and get information from a CD/DVD, when you set the image to be floppy-disk emulated? Does the floppy-disk image use a FAT12 filesystem on the floppy-disk image and then use code to load files from the CD/DVD? Or do you just ignore FAT12 all together and just use code to load parts of the CD/DVD/ISO? or what?

The floppy disk emulation was designed to be used with a floppy disk image containing DOS, MSCDEX, and a CD driver.

You can put whatever you want in the floppy disk image. You don't even have to use FAT12. However, those DOS disks never used the BIOS to access the CD, which means you probably can't use the BIOS to access the CD.

saltlamp wrote:
I was reading a Wikipedia page on 'El Torrito', (https://en.wikipedia.org/wiki/El_Torito_(CD-ROM_standard)) and it said that when in floppy-emulation mode, it acts as a virtual floppy-disk, but then it said before that when in hard-disk emulation mode, it get information directory from the CD/DVD. So is it only for hard-disk emulation, or is the same for both, but it is just say, or is there is mechanism to get information from the CD/DVD/ISO using a floppy-disk? Or do I just not understand something here

I'm not sure I understand your question here. Both emulation modes are the same, aside from the type of disk being emulated. You can only access the contents of the emulated disk.


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 Post subject: Re: Help with getting files from a floppy-emulated CD/DVD/IS
PostPosted: Sun Jan 13, 2019 12:47 pm 
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Octocontrabass wrote:
saltlamp wrote:
How do you read and get information from a CD/DVD, when you set the image to be floppy-disk emulated? Does the floppy-disk image use a FAT12 filesystem on the floppy-disk image and then use code to load files from the CD/DVD? Or do you just ignore FAT12 all together and just use code to load parts of the CD/DVD/ISO? or what?

The floppy disk emulation was designed to be used with a floppy disk image containing DOS, MSCDEX, and a CD driver.

You can put whatever you want in the floppy disk image. You don't even have to use FAT12. However, those DOS disks never used the BIOS to access the CD, which means you probably can't use the BIOS to access the CD.

saltlamp wrote:
I was reading a Wikipedia page on 'El Torrito', (https://en.wikipedia.org/wiki/El_Torito_(CD-ROM_standard)) and it said that when in floppy-emulation mode, it acts as a virtual floppy-disk, but then it said before that when in hard-disk emulation mode, it get information directory from the CD/DVD. So is it only for hard-disk emulation, or is the same for both, but it is just say, or is there is mechanism to get information from the CD/DVD/ISO using a floppy-disk? Or do I just not understand something here

I'm not sure I understand your question here. Both emulation modes are the same, aside from the type of disk being emulated. You can only access the contents of the emulated disk.


Sorry if I wrote in a confusing way; I was bored and getting a little bit frustrated over Mkisofs not working properly when I was trying to create a no-emulated image.

Anyway. using drivers to access the disk from the emulated disk answered my question. Thanks!


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