Atari ST series Technical Reference Manual page 259

Set Default Drive Number
Dsetdrv()
T h e d e f a u l t d r i v e is t h e o n e G E M D O S a s s u m e s is r e f e r r e d to w h e n o n l y a
f ile n a m e is u s e d . T h is f u n c t i o n a l l o w s y o u t o s e t t h e d e f a u l t d r i v e , a n d r e ­
tu r n s i n f o r m a t i o n a b o u t t h e n u m b e r o f lo g ic a l d r i v e s r e c o g n i z e d b y th e
s y s t e m .
C macro format
l o n g d r i v e s ;
i n t d e f a u l t ;
d r i v e s = D s e t d r v ( d e f a u l t ) ;
Machine language format
m o v e . w # d e f a u l t , - ( s p )
m o v e . w # $ 0 E , - (s p )
t r a p # 1
a d d q .l # 4 , s p
Inputs
w o r d
d e f a u l t
Results
l o n g
DO d r i v e s
See also
D g e t d r v ( ) , D s e t p a t h ( )
Dsetdrv
T h e n u m b e r o f th e d r i v e to s e t a s t h e d e ­
f a u lt (d r i v e A : =
o n ) .
A b it f la g t h a t i n d i c a t e s w h i c h d r i v e s a r e r e c o g n i z e d
b y th e s y s t e m . E a c h b it t h a t c o r r e s p o n d s t o a k n o w n
d r i v e is s e t t o 1 (b it 0 =
a n d s o f o r t h ) .
Opcode = 14 ($0E)
0 , d r i v e B : = 1 , a n d s o
d r i v e A : , b it 1 = d r i v e B :,
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