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Bootable DMF diskette?

Have you already compressed the executables? pklite, lzexe, upx, etc.? (Don't compress command.com, it doesn't work)
I have not, do they still run-on-the-fly when compressed in this manner? My reaching for this pair of disks implies there is no hard disk drive, or that it has not been set up properly.
 
Yes, compressed .EXE/.COM files decompress into memory at runtime without additional software; they run normally, but just take up less disk space. I would grab UPX and give it a shot. (If you intend for your boot disk(s) to be used on an XT-class system, be sure to use the upx compression option that enables that, otherwise they'll hang on such systems.)
 
Yes, compressed .EXE/.COM files decompress into memory at runtime without additional software; they run normally, but just take up less disk space. I would grab UPX and give it a shot. (If you intend for your boot disk(s) to be used on an XT-class system, be sure to use the upx compression option that enables that, otherwise they'll hang on such systems.)
I don't plan to use it really on anything below a 286, but thanks. I'll have a look later tonight!
 
Hello all, I have a pair of floppy diskettes which I use for disk repair and data recovery, one is packed as full as it can be (2048 bytes free) and the other is basically empty (<200K on disk), thus it has occurred to me that I could probably condense this into one floppy if I switch to a different disk format. The disk is only useful on x86 machines with a 3.5" drive so there are no concerns about compatibility with other machines to be had.

It seems like the best choice is to use DMF to get ~1.68MB out of a diskette. This would be more than enough to hold everything I want and more. I checked, in WinImage, a DMF 1.68MB image with every file from both disks leaves me with around 250K free.

This is easier said than done, however, and that's where I come asking for help:
2M and fdformat will successfully format a disk at DMF 1.68MB, but will not make it bootable. fdformat lists this as an invalid option and it appears that 2M does not even attempt, and so is probably an invalid option as well.
Trying with WinImage under Windows 98SE it will write the image to the disk flawlessly - It is readable under 9x on two different machines I have access to and by DOS booted from floppy and hard disk. Perfect. However, it will not boot itself. The machine just says "Non-system disk or disk error" and makes me retry.

In WinImage, I tried both the "95/98" and "DOS6.22" boot sector options to no avail. I tried formatting a blank disk as bootable in 98SE, imaging it, and changing it's format to no avail. I then read the formatted disk in WinImage and saved just the boot information to be applied to the other image - No luck. I also tried saving the boot information from the working 1.44MB disk and applying it to the larger image - also no change.

Am I missing something or am I just crazy? I seem to remember Windows 95/98 setup disks that were 1.68B, 1.72MB and still bootable! I would prefer the 1.68MB format because that still allows access in Windows NT.
If there's no other way to do this, what are some other (lightweight!) ways to get a few extra K's from my disk? It's very inconvenient to disk swap in single drive systems. The less startup time and memory usage, the better.


On a semi-unrelated note, fdformat's sector skewing is fantastic and improved boot time by almost half on the 1.44MB disk, so this wasn't a total waste of my afternoon, at least.

Thanks for reading.
If I think back IBM PC-DOS 7.0 had the 1.7 MB floppy's but the 1st install disk was 1.44MB must have had some kind of driver or something to tell the BIOS and the only way I could make a backup set was with Disk Copy Fast or DCF5.3
hope that helps
 
Hello all, I have a pair of floppy diskettes which I use for disk repair and data recovery, one is packed as full as it can be (2048 bytes free) and the other is basically empty (<200K on disk), thus it has occurred to me that I could probably condense this into one floppy if I switch to a different disk format. The disk is only useful on x86 machines with a 3.5" drive so there are no concerns about compatibility with other machines to be had.

It seems like the best choice is to use DMF to get ~1.68MB out of a diskette. This would be more than enough to hold everything I want and more. I checked, in WinImage, a DMF 1.68MB image with every file from both disks leaves me with around 250K free.

This is easier said than done, however, and that's where I come asking for help:
2M and fdformat will successfully format a disk at DMF 1.68MB, but will not make it bootable. fdformat lists this as an invalid option and it appears that 2M does not even attempt, and so is probably an invalid option as well.
Trying with WinImage under Windows 98SE it will write the image to the disk flawlessly - It is readable under 9x on two different machines I have access to and by DOS booted from floppy and hard disk. Perfect. However, it will not boot itself. The machine just says "Non-system disk or disk error" and makes me retry.

In WinImage, I tried both the "95/98" and "DOS6.22" boot sector options to no avail. I tried formatting a blank disk as bootable in 98SE, imaging it, and changing it's format to no avail. I then read the formatted disk in WinImage and saved just the boot information to be applied to the other image - No luck. I also tried saving the boot information from the working 1.44MB disk and applying it to the larger image - also no change.

Am I missing something or am I just crazy? I seem to remember Windows 95/98 setup disks that were 1.68B, 1.72MB and still bootable! I would prefer the 1.68MB format because that still allows access in Windows NT.
If there's no other way to do this, what are some other (lightweight!) ways to get a few extra K's from my disk? It's very inconvenient to disk swap in single drive systems. The less startup time and memory usage, the better.


On a semi-unrelated note, fdformat's sector skewing is fantastic and improved boot time by almost half on the 1.44MB disk, so this wasn't a total waste of my afternoon, at least.

Thanks for reading.
I'm able to boot from diskettes formatted with fdformat (I prefer not to use skewing as I had problems with it).

fdformat /f172 /s

Did you try this?
I think some drives are not capable of booting from these disks, while others are.

I'm positive that 2M formatted disks definitely don't work as they need the TSR loaded to work.
 
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