Re: 800KB DD disk reliability in SuperDrives?

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

MdntTrain <js@cimmeri.com> wrote:

> Warren,
> 
>   I just recently conducted a similar test for a drive repair I'm
> doing, and had no issues.. albeit I'm not using a Superdrive
> controller.. but rather had a Superdrive daisy-chained into an 800k
> plugged into my IIgs.
> 
>   The steps I took were to format + verify an 800k floppy in the 800k,
> then switch it over to the SD, and first verify it, then reformat +
> verify... then put it back in 800k, verify + format + verify... this
> loop about 5 times repeated.   I had perfect results between the 800k
> drive and SD drive.. as I was expecting to see.
> 
>     This drive was intended to be used in this manner for the Macs..
> of which the 800k type, the IIgs has an identical floppy port... so I
> don't understand Geoff's comment re it not being unusual for this type
> of use to fail.

Easy to explain: the problem isn't with the SuperDrive itself, but the
firmware on the card.

I already knew of the formatting bug with mixing 720K and 800K disks (it
effectively remembers the physical disk format based on the last read,
and the format operation fails if you try to format an 800K disk after
having just read a 720K one, or vice versa).

It seems that there is also a general problem with formatting 800K
disks. I'll have to test this myself for personal curiosity and
verification (need to find some spare floppies first).

-- 
David Empson
dempson@actrix.gen.nz