Covering the hole is only a short-term solution. The magnetic properties of the two disk types are slightly different, so long-term storage of 800K info on a 1.4MB disk is not recommended.
Some people have good luck with it, others not so much. Your mileage may vary. :-) ----- Original Message ----- From: "Cyrus" <[email protected]> To: "Vintage Macs" <[email protected]> Sent: Tuesday, February 10, 2009 8:03 PM Subject: Re: 800k 3.5" disk drive for PowerMac 7100 Ah! Thanks, I figured it was something like that. -Cyrus P.S. Would covering the hole make it work? P.P.S. Sorry to change the subject; I thought that maybe both subjects might be related. :-) On Feb 10, 5:59 pm, "Bob C." <[email protected]> wrote: > Cyrus, > > The 800K drive in the Mac Plus cannot tell the difference between a true > 800K disk (DSDD) and the newer 1.4MB disks (DSHD), so it always formats them > as 800K (a proprietary format that used 4 different speeds and differing > numbers of sectors per track). > > When the "SuperDrive" or "FDHD" was introduced, it included an extra little > switch that would sense the presence of the additional hole in a 1.4MB disk, > and adjust the formatting accordingly. The 1.4MB format was more of an > industry standard with one speed. > > So, if you format a 1.4MB capacity disk in a Mac Plus, it will incorrectly > format it as an 800K. Then, when you put that same disk in an FDHD or > SuperDrive, it will see the extra hole, think it should be 1.4MB, find out > that it's not formatted correctly, and say that it needs to be formatted. > > The moral of this story? Don't use modern 1.4MB floppy drive blanks in a > Mac Plus. :-) > > ----- Original Message ----- From: "Cyrus" > > Does it work the other way? I have a Mac Plus, and it seems to be able > to format a 1.44Mb disk sot that it can read it, but then none of my > other macs (IIsi, G3 minitower) will read it, and if I format the > disks on the newer macs, the Plus won't read them. > > -Cyrus --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/vintage-macs?hl=en Low End Mac RSS feed at feed://lowendmac.com/feed.xml -~----------~----~----~----~------~----~------~--~---
