User`s guide
INTRODUCTION
The
1541
disk drive greatly increases the speed , storage capacity, flexibility and reliabil-
ity
of
your Commodore computer. As you use the
1541
disk drive, you will appreciate its
superiority to the cassette recorder you may
have useq before and
to
disk drives offered for
other brands
of
computers.
The 1541-D disk drive
ia
fully compattl>le with the commodore 1541 disk drive, therefore
we
may often omit the "-II" auftlx throughout the remainder
of
thia manual.
THE
ADVANTAGES
OF
A DISK DRIVE
• Speed
If
you have used a cassette recorder for data storage, you probably know it can take up
to
an
hour just to search one long cassette tape looking for a specific program. With the
1541
disk drive, a list
of
all the programs on a diskette appears on your screen
in
seconds. The speed
of
program loading is also greatly improved. It takes the
1541
only
a minute to load a large program that would take a half-hour to load from tape.
• Reliability
Reliability
is
another reason for choosing a disk drive. It
is
all too common for a cassette
user to accidentally erase a valuable program by saving a new program on top
of
the old
one, without realizing it. The
1541
disk drive automatically verifies everything
it
records.
• Direct File Access
A third advantage
of
a disk drive
is
the ability to use relative files (discussed
in
Chapter
6).
On a diskette, any part
of
a relative file can
be
accessed and altered separately,
without affecting the rest
of
the file.
Overall, using a disk drive makes for easier and more powerful computing.
FEATURES
OF
THE
1541
The
1541
is
one
of
the most affordable disk drives on the market. Compared to
competitors, the
1541
has high capacity, and even higher intelligence.
It
is
one
of
the most
cost-effective disk drives available. Most home and personal computers that use a disk
take at least
!OK
of
RAM memory from the computer
to
hold a disk operating system
(known as a
DOS.) This large program must be
in
memory the whole time the disk is
bei_ng used, and much
of
it
must also be kept on every diskette.
The Commodore
1541
works differently and more effectively. It contains
it
s own
built-in microcomputer to control
it
s various operations, along with enough
ROM
and
RAM memory
to
operate without any help from the computer. Commodore
's
DOS
"lives"
entirely inside the disk drive, and does not require any internal memory
in
th
e
computer to do its work , nor does
it
have
to
be
loaded before use like DOS on other
computers.
It
is
so independent that once
it
begins working on a command,
it
will
complete
it
while the computer goes on to some t)ther task, effective
ly
allowing you
to
do
two things at once.