formatting MFM drives on a IBM PC

Jon Elson elson at
Thu Sep 28 11:04:29 CDT 2017

On 09/28/2017 10:31 AM, Chuck Guzis via cctalk wrote:
> And even the sector size on recent drives is fictitious. 
> Larger drives use 4K sectors but "translate" them to the 
> 512 byte standard.
So, for every write, it needs to read the 4K sector, alter 
the bytes and then rewrite it?  Hmmm, explains why writes 
are slower than reads even on spinning disks.  Of course, if 
you write entire tracks, it can just hold the partial data 
until it has all the data for that track, and write out the 
buffer in one rotation.


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