Request: Hard-sectored disks (5.25) for test material to KF team

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Request: Hard-sectored disks (5.25) for test material to KF team

Post by Rakki » Sat Dec 09, 2017 8:28 pm

Kryoflux team is looking for hard sector floppies (5.25") for test material to improve Kryoflux software support.

So far we have heard about 5, 6, 7, 8 and 13 index holes hard sector disks. All kinds of hard sectored disks are welcome but most importantly they should be good working order and run on real system. Disks must have more than one index hole - otherwise it is soft sectored. See the link below so you can see the difference.

Soft vs hard-sectored floppy: ... ctored.jpg

Northstar and Heath were commonly known to use hard-sectored floppies but is there other systems? Apple II used sometimes hard-sectored floppies because its disk drive doesn't have the sensor for index hole at all. Especially if there's PC based systems that actually used hard-sectored disks are very interesting.

If you have got test material please reply to this thread. For more details like shipping addess we can use forum's private messages.

Based on Stack Exchange answer:

Hard sectored 8" and 5-1/4" floppy disks were used in some early computers including:
  • DEC Pro 350
  • Heath/Zenith H-89a
  • MITS Altair 8800BT
  • NorthStar Horizon
  • Vector Graphic computers
  • Processor Technology add-on for the Sol-20 computer called the Helios II Disk Memory System
  • Compudata Exidy Sorcerer add-on floppy drive based on the Micropolis
  • Quite some of the Zilog dev systems (MCZ 1/15, MCZ 1/30, MCZ 1/05)

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Re: Request: Hard-sectored disks (5.25) for test material to KF team

Post by IFW » Mon Dec 11, 2017 10:39 pm

We are looking to at least support reading data written to hard-sectored disks for systems that actually did not use the index signal at all - ie many 8-bit systems.
Apparently, it was at one time popular to write onto these disks, simply because they became dirt cheap after the hard-sectored format was pretty much abandoned in favour of the soft-sectored formats, and it did not matter for drives which did not use index signals anyway.
We might be also looking into supporting "real" hard-sectored formats (where the sector index information was actually used), but reliable/low-level information is pretty scarce on those, and we simply do not have any such disk.

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