Re: Profile drive question

[dempson@actrix.gen.nz (David Empson)]

Ernest <ernestls@home.com> wrote:

> What kind of hard drive did the Profile 5mg  use?

The 5 MB version used a genuine Seagate ST-506 mechanism (MFM, with the
same physical interface as used by an IBM XT, now generally called the
"ST-506" interface).  I expect that the 10 MB version used the
equivalent 10 MB Seagate model.

> If I have one with a dead HD, what could I replace it with?

Not much except the original mehcanism.  In theory, you could change
between 5 MB and 10 MB, but I've never heard of anything larger being
used, unless you rip the guts out of the case and basically use it as a
power supply for a drive with a different interface.

The big problem is that if you replace the mechanism you will need to
reformat the drive, and that requires an Apple III with an Apple III
Profile controller card, special partitioning software, and a special
CPU/PROM which needs to be installed in the drive's controller card.
The partitioning software and the CPU/PROM must match each other and are
tied to a specific drive capacity.

The CPU/PROM is typically a prototyping version of the Z8 single-chip
microprocessor which supports a piggyback 2716 EPROM.