Casio IT-2000W Technical Reference Manual page 73

Key Operation
2 or 8 key Selects the objective item (drive selection screen).
0 key Does not perform formatting (formatting start screen).
1 key Starts formatting (formatting start screen).
Toggles YES and NO options of formatting.
. (decimal) key
RET key Confirms the current setting.
CLR key Cancels the current setting.
Others Invalid.
Function
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