Atari ST series Technical Reference Manual page 251

Send Character to RS-232 Port
Cauxout()
T h is f u n c t i o n s e n d s a s i n g l e c h a r a c t e r to t h e R S - 2 3 2 s e r i a l d e v i c e . I t d o e s
n o t r e t u r n u n til t h e c h a r a c t e r h a s b e e n s e n t .
C macro format
c h a r c h ;
C a u x o u t ( c h ) ;
Machine language format
# c h , — (s p )
m o v e . w
m o v e . w
# 4 / - (s p )
#1
tr a p
a d d q .l # 4 , s p
Inputs
c h w o r d
Results
N o n e
See also
C a u x o s ( ) , C p m o u t ( ) , C c o n o u t ( )
Cauxout
T h e l o w b y t e c o n t a i n s t h e A S C I I v a l u e o f
t h e c h a r a c t e r to w r i t e t o t h e s e r i a l p o r t ,
t h e h i g h b y t e is 0 .
Opcode = 4 ($04)
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