INTRODUCTION
The
Apricot
incorporates
the
SN 76489
sound
generator
chip,
which
has
four
sound
channels.
Two
of
these
are
used
by
the
bell
and
the
keyboard click, leaving
two
for
the
user.
The
BIOS
controls
the
software aspect of
the
sound,
including
both
initialization
and
execution.
The
Keyboard
click is achieved
through
the
white-noise
channel
of
the
chip,
while
the
bell
uses
one
of
the
square
wave
channels.
APPLICATIONS INTEREST
The
Sound
Generator
is accessed
from
Port SOH,
the
program below
will
playa
short
four-note
tune:
10
DATA
9,128,15,149,168,7,182,192,5,215
20
DATA
9,136,12,149,164,6,182,195,4,215
30
DATA
9,128,10,149,160,5,182,197,3,215
40
DATA
9,136,07,149,172,3,182,200,2,215
50
DATA
4,159,191,223,255,255,255,255,255,255
60
FOR
K=l
TO
5
70
FOR
L=l
TO
10:READ
A
80
OUT
&H50,A:NEXT
90
FOR
L=O
TO
2qO:NEXT
'Delay
100
NEXT
'e
'D
'E
'F
'no note
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