On 7/20/2012 9:26 PM, Michael J. Mahon wrote:
Because so-called DOS-ordered images are written in DOS *logical* sector order, not physical sector order.
This sounds crazy to me. Let's reiterate so that even a hardware guy can understand.
On a physical floppy the sectors have address markers. The position of any sector can only affect the speed of access, not the logic. DOS 3.3 has a skew table, so if it wants to get a logical sector 1 it finds a physical sector D in the table and waits for the address marker D. Am I right so far?
So a program running on an emulator doesn't know it's an emulator and does the same: waits for the address D when it wants sector 1 *logical*. So it would be logical (pun intended) to keep data in the .DSK file consecutive and assign nibble address markers according to the physical address of the given block of 126 bytes, right?
What am I missing here? -Alex.