>Can someone explain how the Apple II GCR worked? I tried deciphering this
>several years ago and I could figure it out (the only references I found
>were very vague).
There's one reference which is extremely non-vague: _Beneath Apple
DOS_, by Don Worth and Peter Lechner. In it you'll find wonderful
illustrations featuring Sir Isaac Newton and leading you through the
wonderfully intertwined world of the Disk ][ state machine, 6502
machine code, and modulation formats. This book is still available
new (see my past posts to comp.sys.apple2 for details on how to buy it.)
If you're too cheap to buy the book (again, buy the book! It's
worth every last cent!), the relevant section of it (minus the
cute drawings) is online at
http://www.umich.edu/~archive/apple2/misc/hardware/disk.encoding.txt
But, again, buy the book! Woz is not my super-hero, but he could do
amazing things with a half-dozen TTL chips, that everyone else was
doing with a hundred or more...
--
Tim Shoppa Email: shoppa_at_trailing-edge.com
Trailing Edge Technology WWW: http://www.trailing-edge.com/
7328 Bradley Blvd Voice: 301-767-5917
Bethesda, MD, USA 20817 Fax: 301-767-5927
Received on Wed Apr 07 1999 - 20:04:11 BST