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3

Generally, most 1996 mainboards WILL deal with a 5 1/4" floppy just fine IF you use the appropriate cable (which will often NOT have been supplied with a computer or mainboard in 1996). The important thing is BIOS support. Which is likely on any mainboard that still has ISA slots. IIRC I did use a 5 1/4" drive just fine on a ca. 1998 ASUS P5A based system, ...


0

Profit for vendors of preformatted disks :) IIRC, many such disks failed when you actually reformatted them (certainly more often than those originally sold unformatted), making it appear like selling them preformatted actually was a method of reusing partially defective media respectively achieving higher production yields.


2

For Apple II diskettes, some games used one "sector" per track, thus using all the sector header and inter-sector space on each track for more data. This is because all the sectoring was "soft" and done strictly in software (custom RWTS code).


0

I guess you can't format say, track 81, start to read that track, then move to a target track formatted in Amiga format on the same drive and continue reading?


14

The answer will depend on the exact model of 300PL you have, but there’s a good chance it will be possible to use a 5.25” drive with your computer. Many 300PL models, such as type 6592, type 6565, and your type 6862, explicitly support 5.25” drives, and support connecting two drives at once; so with one of those, you should be able to connect the drive, ...


2

The HxC/Gotek floppy emulators are designed to work with a Shugart type floppy interface, which was widely used in many retro-computers, but is not directly compatible with the Apple ][ floppy controller. The video you linked notes in the description that both the HxC firmware was replaced and a new cable/interface was created in order to make the floppy ...


6

The "busman's punch" from Solar Mike's comment was common in the 8 inch days. Disks were sold as "SSSD" (Single Sided, Single Density) and there was a hole in the sleeve near the hub, offset from the head slot, aligned with an optical sensor. When a hole in the disk passed under this hole. the sensor generated an "index pulse" to signal the start of a track. ...


3

Someone used to make disk drives that spun faster when the head(s) were on outer tracks, so that those tracks could hold more bits. Correction: slower, not faster (see comments).


3

Each track of a normal floppy disk contains one repetition per sector of the sequence: Sync pattern; sector header; short space; sync pattern; sector data; longer space When a computer is asked to read a sector, it looks for a sync pattern followed by a header for the desired sector. It will then ask the controller to look for a sync pattern and grab ...


15

Floppy disks store data on each side, in tracks, each track split into sectors, with gaps between each sector. On top of that comes the file system, FAT for DOS-compatible systems, which defines how data is stored in sectors, and how much space is used for metadata. Based on this, using the PC’s disk controller, there are two main ways to increase a floppy’...


21

420K was common for 360K floppies (not only on PC) it was done like this: increasing number of sectors original format has 9 sectors per track but there is space for 10 (the physical gaps are smaller but the formatted gaps are still the same). increasing number of tracks original format has 40 tracks but floppy is big enough and most (I mean all) drives ...


3

Both Microsoft and IBM had their own distribution disk formats. Microsoft had DMF, which allowed the disk to contain 1680 kB of data on a 3½-inch disk, instead of the standard 1440 kB. It was used for software distribution. It worked by increasing the cluster size and sector count but cutting down the FAT. IBM used XDF format for software distribution, ...


7

There were tools such as 2M and fdformat that were able to use non-standard floppy formats. The data rate is fixed, but by shortening the gaps between sectors it was possible to increase the number of sectors per track. On some drives it was also possible to increase the amount of tracks on the disk, but it depends on the actual drive how many if any extra ...


5

There's a recent improvement in C64 fast loading technology made by Linus Åkesson. The main idea is to decode GCR inside 1541 thus gaining more transfer speed. An introductory article into the problems of GCR decoding inside 1541 (with the memory for both code and data of just 2048 bytes) is here: https://www.linusakesson.net/programming/gcr-decoding/index....


20

You can actually read about 98% of an Amiga disk with a PC controller and just one drive, but at risk of destroying 2% of the data. The two-drive solution overcomes these limitations. Credit for the two-drive trick should probably go to Vincent Joguin, who first implemented this in 1999. He applied it to NEC's floppy controller, but others are compatible ...


5

Here are the ones I've come across: SDOS V1.1, a "C64 disk utility and speed loader," which has had development done on it as recently as 2019. According to the readme, it's "Public Domain: open-source and freeware." It's based on earlier programs "VDOS" (1986), "SJLOAD (v0.96)" (2008-2009) and "SDOS (v1.0)" (2016). I discovered it on csdb.dk, but the ...


68

This only works with 2 drives on the same controller and cable. The floppy controller doesn't know when the disk (hardware) has been switched on the port (software), so a transfer command can be issued on the IBM formatted disk, but run on the Amiga disk. This answer comes from the documentation for the utility Disk2FDI. Here's an excerpt from docs\tech\...


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