🚀 go-pugleaf

   I'm new to the hard disk game. I should be getting my first ever, in about
a week for my ST (primarily for Minix use.) It'll be a TCT 65Mb. However,
I'd like a few questions about hard drives answered, if possible...

1. What controls the data transfer rate for a drive?
   I am led to believe that this is in the hands of the controller. After
   reading the documentation that comes along with the ICD utilities I was
   susrprised to learn about data transfer rates ranging from 300Ks to 1010Ks.
   What's the big difference with these controllers. Does the 1010Ks one cost
   the price of a small island in the Pacific?

2. I've heard that hard drives spin at about 3600 rpm. Therefore if your
   recommended interleave factor is one, will the controller read the track
   in a single revolution? If so doesn't that mean it is reading the track
   in 1/3600th of a second? (This can't be right!) I know the seek and
   latency times come into this, but if we just talk about the transfer rate
   i.e. the head sits over one track and just keeps continualy reading it, then
   why then can't it read the track 3600 times a second? I'm pretty sure this
   isn't what happens, but could someone explain why?

3. Also, when given a list of bad sectors, what does the controller do with
   it? Does store this info. somewhere on the disk so that in the future, it
   appears to all software that the disk has no bad sectors? Reference this
   to the Adaptec RLL controller if possible, as that's the one that comes
   in the TCT drives.

I'd appreciate any info. on hard disks that anyone can supply. Thanks.
Reply to the net as I think other people may find the info. of some use.
(also a CC: by e-mail if possible as news quite likes to go down, here.)

Mark Powell

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