Atari ST series - Page 191

Bcostat
Get Output Device Status
Bcostat() Opcode = 8
B c o s ta t() tells y o u w h e th e r a p articu lar o u tp u t d ev ice is re ad y to ac ce p t a
ch ara cter. It can b e u se d to av o id "h a n g in g " y o u r p ro g ra m u p by sen d in g
a ch a ra cter to o n e o f th e o u tp u t ro u tin es w h e n th e d ev ice is n o t re ad y.
C macro format
in t d ev n u m ;
lo ng statu s;
statu s = B co sta t(d e v n u m );
Machine language format
m o v e, w # d e v n u m / - (sp )
m o v e.w # 8 , - (sp )
tra p # 1 3
ad d q .l # 4 ,s p
Inputs
d e v n u m w o rd T h e d ev ice n u m b er of th e in p u t d ev ice
w h o se ou tp u t sta tu s is te sted :
0 = P R N : (P rin ter p ort)
1 = A U X : (R S -232 p ort)
2 = C O N : (C o n so le s c re en )
3 = M ID I: (M ID I o u tp u t)
5 = IK B D : (In tellig e nt k ey b oard co n 
tro ller)
Results
DO s ta tu s lo n g T h e o u tp u t sta tu s o f th e d ev ice:
0 = n o t re a d y to rece iv e a c h a ra cte r
- 1 = re ad y to re ceiv e a ch ara cter
See also
B c o n o u t(), B c o n in ( ), B c o n s ta t()
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