Is fast stepping used in the 1541?
Date: 2008-07-31 11:42:11

Hallo allemaal,
Just for fun I was looking if I could speed up the 1541 inside Gideons
1541 Ultimate. The idea was that to skip all delays caused by mechanical
features. For example, the start-up time for the motor can set from $3C
to 1. Should Work fine as I already use this feature in my 1541IDE
The next delay is the one for stepping the head. As I don't use any head
stepping at all, I simply removed all routines. But Gideons 'floppy
drive' does act on the state of the outputs of the 6522 and so I need at
least the routines that output the signals for the stepping motor. 
There is a routine for fast stepping the head and one for slow stepping.
The actual decision is made at $FA0E where the number of steps is
compared with MINSTP ($0064). MINSTP is filled with the value $C8 = 200
at position $F2A4. What ever the original input is, at $FA0E register A
is a number where bit 7 = _always_ zero. And therefore A can never be
greater then $C8 and thus the fast stepping routine is never executed. 
Or am I wrong? 
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