Using The Cassette Recorder; Program Storage - Commodore VIC-20 User Manual

"APPENDIX B"
USING THE CASSETTE RECORDER
The cassette recorder acts as the VtC's "memory1*. Without this
device, the VIC will forget any program you typed in as soon as the
power goes off tor someone uses the NEW command). You can also
use the recorder for programs you purchase. Commands used with
programs on tape are SAVEH LOAD, and VERIFY.
The VIC can also "remember" the values of variables and other
items of data, collected in a group called a file. The amount of data
stored in a file can be very large compared to the amount of RAM in
the V!C, because the VIC can operate on a small piece of the file at
a time. Statements used with data files are OPEN, CLOSE, PRINT#,
INPUTS and GET#. The system variable ST (status), is used to
check for tape markers.
PROGRAM STORAGE
Let's say you have just finished creating a new program on the VIC.
You will want to use the program again at some other time, so now
you must store it on the tape. Type the word SAVE. If you want the
program to have a name, type a quote mark (if) and the program
name. The name can contain graphics and cursor controls, and can
be up to sixteen characters long. Then just hit the RETURN key,
whether you gave it a name or not.
If your recorder is plugged into the back of the VIC, and none of its
buttons are pressed down, the following message will appear on the
screen:
PRESS PLAY AND RECORD ON TAPE
All you have to do now is put a blank cassette tape (any decent
audio tape will do) in the recorder. Hold down the RECORD key and
hit PLAY on the recorder. The tape should start moving, and the
following message will appear on the screen:
OK
SAVING name
What the VIC is doing now is recording, with a very fast series of
high and low sounds, your program in RAM onto the tape. The
program is not being disturbed at all, it is just being copied. The
VIC actually records the program twice, just in case your blank tape
isn't perfect. When the program is all on the tape, the VIC stops the
recorder (all by itself!) and gives the READY message.
Now you may wish to check the tape to make sure that the SAVEd
program is correct. After all, you are risking much of your valuable
time to an uncertain piece of thin magnetic tape. It is better to be
safe and check the program.
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