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Re: Iomega Zip drive MFM or GCR?



Another additional thing is PRML or extended PRML (EPRML).
The zip disk would resemble a hard drive more then a floppy disk in the 
encoding scheme.


"Rick Balkins" <rickbalkins.nospam@nospam.gmail.com> wrote in message 
news:4Myil.3090$xm4.456@newsfe20.iad...
> It is probably an RLL scheme. MFM is for FAT/FAT12 disks. 5.25" & 3.5" 
> floppy disks and very early hard drives. New hard drives uses an RLL 
> scheme. If anything, for legacy sake, this would be an MFM/RLL style 
> scheme versus a GCR/RLL scheme.
>
> FAT was built around and on top of MFM coding so it is probably founded on 
> this scheme for later FAT file systems for ease of software and hardware 
> mechanics. If you take a look at Iomega SuperDisk project, it alludes to 
> MFM and MFM/RLL encoding scehemes versus GCR because it doesn't read older 
> GCR disks but MFM disks. So, this is probably the case.
>
> GCR was Commodore, Apple II, and few IBM based systems: 
> http://en.wikipedia.org/wiki/Group_Code_Recording
>
>
>
> "Thomas Richter" <thor@math.tu-berlin.de> wrote in message 
> news:gm8ril$e77$1@infosun2.rus.uni-stuttgart.de...
>> Jack Tseng schrieb:
>>> Iomega Zip disk itself is MFM or GCR ?
>>
>> It is whatever Iomega chose it to be, probably neither of the above. It
>> is rather irrelevant, you cannot access the drive at this level anyhow,
>> it either talks SCSI or ATA commands.
>>
>> So long,
>> Thomas
>
>