Atari ST series Technical Reference Manual page 211

Write String to MIDI Port
Midiws()
T h is f u n c t i o n s e n d s a s t r i n g o f c h a r a c t e r s o u t t h e M I D I p o r t .
C macro format
in t b y t e s ;
lo n g b u f f e r ;
M i d i w s ( b y t e s , b u f f e r );
Machine language format
m o v e .l b u f f e r , - ( s p )
m o v e . w # b y t e s , - (s p )
m o v e . w # 1 2 , - ( s p )
tr a p # 1 4
a d d q .l # 8 , s p
Inputs
b u f f e r l o n g
b y t e s
w o r d
Results
N o n e
See also
I k b d w s ( )
n e w p a g e
Midiws
T h e a d d r e s s o f t h e m e m o r y b u f f e r t h a t
c o n t a i n s t h e c h a r a c t e r s t r i n g to w r i t e .
T h e l e n g t h o f t h e c h a r a c t e r s t r i n g t o w r i t e
( m i n u s o n e ) , in b y te s .
Opcode
12
=