Canon X-07 User Manual page 49

Also, when a key is depressed, a "pip" is heard. This is called a "key click".
This is for checking whether or not a key has been depressed completely.
The key click function can be terminated and restored with the X07-BASIC
CONSOLE command. For example,
CONSOLE"'
Now, the key click has been terminated. To restore it, type
CONSOLE"'
1.6.2 Functions of the special keys
The following explains the functions of the special keys.
RETURN
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