Is there a Catweasel like device for hard disks?

[Jules Richardson]

Andrew Lynch wrote:
> Hi,
> Just out of curiosity, is there a technique or device which can do raw reads
> of tracks on ST506/ST412 style hard disk drives similar to how a Catweasel
> can with a floppy disk drive?

To the best of my knowledge, no - and I've been keeping an ear to the ground 
for such things for a while (plus it's a discussion which crops up here every 
once in a while, but I don't believe anyone's produced any working hardware yet).

The speeds involved (particularly if over-sampling the data) are reasonably 
high - enough that it'd be tricky[1] to throw something together out of OTS 
TTL parts. That puts such a project more within the realm of people who know 
all about interfacing to high speed microcontrollers, and the pool of 
available carbon units with the time, skills and inclination to make such a 
device is pretty darn small.

[1] perhaps impossible. I think some TTL parts will run up to 60MHz or so with 
a good design and layout, but even that is perhaps a bit on the slow side when 
dealing with ST412 drives and doing any reasonable oversampling.

cheers

Jules