Mac 512k Help

#1 Sun, 18 May 2008 - 03:33 68kMLA

Hey guys,

I have a Macintosh 512k machine and a 3.5 Floppy Drive (from my Apple IIgs items). I read that this Mac has a 400K floppy drive built-in, and that the external drive I have can read 800K disks. So I downloaded a System 4.2 disk with Finder 6.0 - made the disk image of that onto an 800K floppy using my Macintosh IIci and put it in the Mac 512k.

The Mac 512k turns to a Happy Mac before switching to a sad Mac (with the code F0064) and ejecting the floppy. This happens when using either disk drive. Any ideas? 8-o

Note: I also tried a System 3.2 / Finder 5.3 disk with the same result.

Any help would be awesome, thanks!

#2 Sun, 18 May 2008 - 03:35 68kMLA

I think to boot properly, you HAVE to use a 400k disk in the internal drive or a 800k disk formatted as 400k.

#3 Sun, 18 May 2008 - 03:41 68kMLA

I think to boot properly, you HAVE to use a 400k disk in the internal drive or a 800k disk formatted as 400k.

Oh ok, any idea how to format a 800K disk as a 400K disk on a Macintosh IIci? The only options I see are: Macintosh 800K, DOS 720K, and ProDOS 800K.

#4 Sun, 18 May 2008 - 03:54 68kMLA

From http://docs.info.apple.com/article.html?artnum=9502

* You can still create an MFS volume on a single-sided disk by holding down the Option key (and keeping it held down until the formatting is complete) when selecting Erase Disk under some versions of System 7, including System 7.0x and System 7.1. However, you cannot create an MFS disk under System 7.5.

So, if you aren't running anything newer than 7.1, you might be able to pull it off.

#5 Sun, 18 May 2008 - 07:57 68kMLA

So I downloaded a System 4.2 disk with Finder 6.0 - made the disk image of that onto an 800K floppy using my Macintosh IIci and put it in the Mac 512k.

You'll want to check this out too:

http://68kmla.org/forums/viewtopic.php?t=1982

System 4.2 is just outside the limit of what we think a 512K will run. You will also need to boot from a 400K MFS disk only. System 3.2 is your best bet here and you will not be able to use that 800K external drive without the HD20 INIT in your system folder. Unless you follow the instructions on this thread:

http://68kmla.org/forums/viewtopic.php?t=1492

Tom Lee's advice is excellent as I did not know that, since it works exactly the opposite way under System 6 and below. I assume when you hold down the option key when selecting erase disk, System 7 will automatically format a double sided disk as 400K MFS (one side only)? Guessing it won't make an MFS 800K disk.

FYI, the external 800K Apple 3.5 drive from an Apple IIGS will boot the 512K, but NOT the UniDisk 3.5 (unless you remove the controller card). The volume can be 400K or 800K, but it MUST be MFS.

#6 Sun, 18 May 2008 - 19:55 68kMLA

Thanks for all the help guys! The System 7 formating trick worked fine. I only could find a very old system - 2 I think. But it worked, even with the external drive.