Tandy 1000 Programmer's Reference Manual page 23

Chapter 1 I System
Calls
Example:
The following program copies the contents of a single sided
disk in Drive A to the disk in Drive
B. It
uses a buffer
of 32K bytes.
p r o m p t
s t a r t
b u f f e r
d b " S o u r c e i n
A ,
t a r g e t i n B",13,10
d b "Any k e y t o s t a r t . 0 "
dw 0
db 6 4 dup ( 5 1 2 dup
( 7 ) )
;64 s e c t o r s
i n
t
-25H : d i s p l a y p r o m p t ; s e e F u n c t i o n
09H
r e a d - t b d ; s e e F u n c t i o n
08H
; c o p y 5 g r o u p s o f
;64 s e c t o r s
mov
C X , ~
c o p y : p u s h c x ; s a v e t h e l o o p c o u n t e r
a b s - d i s k - r e a d 0 , b u f f e r , 6 4 , 5 t a r t ; T H I S
INTERRUPT
a b s - d i s k - w r i t e l , b u f f e r , 6 4 , 5 t a r t
; s e e
I N T 26H
a d d s t a r t , 6 4 ; d o t h e n e x t
64
s e c t o r s
POP c x ; r e s t o r e t h e l o o p c o u n t e r
l o o p c o p y
21