Re: A2 5.25" drive on a PC?

[et472@FreeNet.Carleton.CA (Michael Black)]

Tim Haynes (timhaynes@alumni.NO.SPAM.PLEASE.uwaterloo.ca) writes:
> We all know that a PC cannot read/write an A2 disk because of basic 
> MFM/GCR differences.
> 
> What about the possibility of putting together a specialized cable that 
> would adapt a standard A2 5.25" drive to a PC's serial port?  The cable 
> would also have to pull power from somewhere - possibly from a molex 
> connector hooked into the PC's power supply?  And then we'd need some 
> specialized PC software to actually do the reading/writing.
> 
> Does this seem at all feasible?  Any thoughts?

I just thought of this last week, with the recent thread about reading
Apple disks on a PC.

But when I gave a quick glance for the disk controller manual, I couldn't
find it.  So I didn't take a close look at the schematic.

BUt it would be the parallel port that would likely be the useuable
port, because various control lines are needed, and you have more control
over the lines than with the serial port where it's all pretty fixed.

The Apple II was a pretty limited system compared to current computers.
There may have been a good reason to shift some of the work to the controller
card back then, while today there is bound to be enough computer power to
handle just about anything.

One would have to look over the controller schematic, figure out what's
being done, and how to do that in software.  There may be no way to
eliminate all the hardware; I think of those LS125 drivers that at the
least may be needed (or something like that) to provide enough drive for
the signals going to the actual drive.

Given the simplicity of the original controller card, even if some of
it was needed it wouldn't be much.

   MIchael