View Full Version : Apple Macintosh floppy data format?

May 31st, 2007, 06:15 AM
I just purchased a Fat Mac 512k complete in the carring case with an extra 400k drive. I have a couple of questions.

1. Can I upgrade the internal 400k to an 800K? Should I?
2. Where the heck do you get software. I see very little on Ebay and although I find websites all my other equipment is PC. How do I transfer the stuff?
3. Okay, here is the big one. Does anyone have a technical description of the floppy and/or HD20 data format. I mean both an description of the formats and the electrical waveforms. I want (has this already been done) to build a Pseudo-HD20 out of modern flash memories. It should be easy to set up 20meg of memory but I need to understand how the Macintosh talks to the floppy and/or HD20 to be able to mimic a floppy or HD20 with a microcontroller.

Thanks folks!!

June 26th, 2007, 06:43 PM
1. http://docs.info.apple.com/article.html?artnum=1999&coll=ap

2. old macintosh software :

Working with older disk images
the best way to transfer old stuff is getting a macintosh IIci (they are very commun and cheap) with system 6, so you can read and write, formate MFS-disks with disk copy 4.2 and the computer has a AAUI ethernet port

3. DRIVES Service Manuals

to start up with a 512 k you need the "HD20 INIT" (HD 20 Startup)