Re: it's a FAQ I know, but IIc 5.25" -> anything?

[Ed Eastman <noone@nowhere.net>]

Bryan Parkoff wrote:
>     Do you have the information so it can help me to understand what 
> transition and pulses / non-pulses mean?

After sleeping on it maybe I can explain it this way.   Think of the 
data on an Apple 2 disk as a consistent square wave.  Think of the PC 
disk data as being squished and expanded wave. (pardon the bad ASCII art 
illustrations)

Apple 2 diskette wave is consistent and it detects the high part of the 
wave along row 1.
   ___     ___     ___
1 /   \   /   \   /   \
      |   |   |   |   |
2     |   |   |   |   |
      |   |   |   |   |
3     \___/   \___/   \___/

PC Diskette wave is variable in width and detects the transitions along 
row 2.
   __          __    __
1\/  \  /\  /\/  \  /  \
 ||  |  ||  |||  |  |  |
2||  |  ||  |||  |  |  |
 ||  |  ||  |||  |  |  |
3\/  \__/\__/\/   \_/

In highly simplified terms:  The Apple 2 drive hardware detects the tops 
of the wave, detecting 1s and extrapolating 0s from a consistent timing 
pattern.  The PC drive detects across the middle of the wave, the 
transitions, and measures the time between to determine either the 1 or 0.

Hope that helps in explaining why the PC drive can detect data on the A2 
disk while the reverse has not been proven.

Thankx,
Ed