Tandy 1000 Programmer's Reference Manual page 37

Chapter
1 I System
Calls
AuxInput
Auxiliary Input Function Call 03H
Waits for a character from the auxiliary input device, and
then returns the character in AL. No status or error code
is returned.
If CONTROL-C is typed at console input, Interrupt 23H is
executed.
Entry Conditions:
AH
=
03H
E xi t Conditions:
AL
=
character returned
Macro Definition:
a u x - i n p u t m a c r o
mov a h , 8 3 H
int
2 1 H
e n d m
Example:
The following program prints characters as they are re-
ceived from the auxiliary device. It stops printing when
a n end of file character (ASCII 26, or CONTROL-Z) is
received.
f
u n c - 0 3 H : a u x - i n p u t
; T H I S F U N C T I O N
c m p a l , l A H ; e n d o f f i l e 7
l e c o n t i n u e
; y e s , a l l d o n e
p r i n t - c h a r a 1 ; s e e F u n c t i o n 8 5 H
I m p f u n c - 8 3 H
; g e t a n o t h e r c h a r a c t e r
c o n t i n u e r e t
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