Section 1: Getting Started 17
appropriate prefix key (for example, “Pressing fL …”). References to the
functions shown on the keyboard in gold under the bracket labeled “CLEAR”
appear throughout this handbook preceded by the word “CLEAR” (for example,
“The CLEAR H function …” or “Pressing fCLEARH …”).
If you press the f or g prefix key mistakenly, you can cancel it by pressing
fCLEAR X. This can also be pressed to cancel the ?, :, and i
keys. (These keys are “prefix” keys in the sense that other keys must be pressed
after them in order to execute the corresponding function.) Since the X key is
also used to display the mantissa (all 10 digits) of a displayed number, the
mantissa of the number in the display will appear for a moment after the X
key is released.
Pressing the f or g prefix key turns on the corresponding status indicator – f
or g – in the display. Each indicator turns off when you press a function key
(executing an alternate function of that key), another prefix key, or
fCLEAR X.
Keying in Numbers
To key a number into the calculator, press the digit keys in sequence, just as if
you were writing the number on paper. A decimal point must be keyed in (using
the decimal point key) if it is part of the number unless it appears to the right of
the last digit.
Digit Separators
As a number is keyed in, each group of three digits to the left of the decimal
point is automatically separated in the display. When the calculator is first turned
on after coming from the factory – or after Continuous Memory is reset – the
decimal point in displayed numbers is a dot, and the separator between each
group of three digits is a comma. If you wish, you can set the calculator to
display a comma for the decimal point and a dot for the three-digit separator. To
do so, turn the calculator off, then press and hold down the . key while you
press ;. Doing so again sets the calculator to use the original digit separators
in the display.
Negative Numbers
To make a displayed number negative – either one that has just been keyed in or
one that has resulted from a calculation – simply press Þ (change sign). When
the display shows a negative number – that is, the number is preceded by a minus
sign – pressing Þ removes the minus sign from the display, making the
number positive.
