<s>
AppleCD	B-Device
is	O
a	O
range	O
of	O
SCSI-based	O
CD-ROM	B-Device
drives	O
for	O
Apple	B-Device
Macintosh	I-Device
personal	B-Device
computers	I-Device
,	O
manufactured	O
and	O
sold	O
by	O
Apple	O
Computer	O
from	O
the	O
late	O
1980s	O
to	O
late	O
1990s	O
.	O
</s>
<s>
Earlier	O
AppleCD	B-Device
drives	O
required	O
a	O
CD	O
caddy	O
in	O
order	O
to	O
be	O
used	O
,	O
while	O
later	O
models	O
used	O
a	O
tray-loading	O
mechanism	O
.	O
</s>
<s>
The	O
original	O
model	O
introduced	O
in	O
1988	O
was	O
simply	O
called	O
the	O
AppleCD	B-Device
SC	I-Device
.	O
</s>
<s>
The	O
AppleCD	B-Device
SC	I-Device
was	O
the	O
first	O
CD-ROM	B-Device
by	O
Apple	O
Computer	O
Company	O
,	O
introduced	O
in	O
1988	O
.	O
</s>
<s>
It	O
uses	O
a	O
front-loading	O
caddy	O
1x	B-Device
CD-ROM	I-Device
and	O
is	O
only	O
capable	O
of	O
Read	O
Only	O
Media	O
.	O
</s>
<s>
This	O
accessory	O
device	O
was	O
only	O
able	O
to	O
read	O
compact	O
discs	O
up	O
to	O
a	O
650	O
MB	O
capacity	O
in	O
five	O
formats	O
,	O
CD-Audio	O
,	O
CD-ROM	B-Device
,	O
HFS	O
,	O
ProDOS	O
,	O
and	O
High	O
Sierra	O
.	O
</s>
<s>
On	O
the	O
rear	O
it	O
has	O
a	O
power	O
switch	O
,	O
power	O
input	O
,	O
two	O
Centronics	O
50-pin	O
SCSI	B-Architecture
outputs	O
,	O
and	O
an	O
audio	O
RCA	B-Protocol
connector	I-Protocol
.	O
</s>
<s>
With	O
appropriate	O
software	O
it	O
would	O
run	O
on	O
any	O
Macintosh	B-Device
with	O
a	O
DB-25	O
connector	O
,	O
or	O
an	O
Apple	B-Device
II	I-Device
with	O
an	O
Apple	B-Device
II	I-Device
SCSI	B-Architecture
interface	O
card	O
.	O
</s>
<s>
The	O
AppleCD	B-Device
SC	I-Device
Plus	O
was	O
Apple	O
Computer	O
's	O
second	O
CD-ROM	B-Device
drive	O
,	O
a	O
replacement	O
for	O
the	O
AppleCD	B-Device
SC	I-Device
which	O
was	O
introduced	O
in	O
1991	O
.	O
</s>
<s>
Identified	O
as	O
model	O
number	O
M3021	O
,	O
just	O
like	O
its	O
predecessor	O
,	O
the	O
AppleCD	B-Device
SC	I-Device
,	O
it	O
used	O
a	O
1x	O
Read	O
Only	O
Media	O
CD-ROM	B-Device
drive	O
.	O
</s>
<s>
The	O
Plus	O
could	O
read	O
a	O
CD	O
with	O
up	O
to	O
750	O
MB	O
of	O
data	O
over	O
the	O
650	O
MB	O
of	O
the	O
AppleCD	B-Device
SC	I-Device
.	O
</s>
<s>
On	O
the	O
back	O
there	O
were	O
two	O
50-pin	O
Centronics	O
SCSI	B-Architecture
connectors	O
,	O
audio	O
RCA	B-Protocol
connectors	I-Protocol
,	O
power	O
input	O
,	O
and	O
a	O
power	O
switch	O
.	O
</s>
<s>
The	O
AppleCD	B-Device
SC	I-Device
Plus	O
had	O
only	O
minor	O
improvements	O
over	O
the	O
AppleCD	B-Device
SC	I-Device
and	O
it	O
was	O
relatively	O
the	O
same	O
.	O
</s>
<s>
They	O
all	O
include	O
two	O
Centronics	O
50-pin	O
SCSI	B-Architecture
ports	O
,	O
and	O
require	O
mains	O
power	O
.	O
</s>
