HP HP-16C - Section 6: Memory and Storage; Converting Storage Registers to Program Memory; Storage Register Size

Section 5: Floating-Point Numbers 61
Floating-Point Arithmetic
Functions
All of the arithmetic functions which operate in Integer mode ([+],
(<], [x], (], [ix]) also operate in Floating Point Decimal mode. The
(¢]and functions are not limited to integer answers in Floating
Point mode.
The (reciprocal) function, which is active only in Floating-
Point Decimal mode, calculates the reciprocal of the number in the
X-register.
The Out-of-Range Flag
The arithmetic functions [+], (-], [x], and [¢] are the only functions
in Floating-Point Decimal mode that affect flag 5 (out-of-range).
Flag 5 is set or cleared whenever these functions are executed.
Executing {0to0 9, (-]} likewise affects flag 5.
The carry flag (flag 4) is not affected in Floating-Point Decimal
mode.
Functions Not Active in Floating Point Mode
Generally speaking, the display and number control functions and
bit manipulation operations are not active in Floating-Point
Decimal mode. Appendix B contains a complete list of all
operations that are not active in Floating Point mode.
Digit Separators
The HP-16C is set to use a period as a radix mark (separating
integer and fractional parts of a number) and a comma between
groups of three integer digits. You can reverse this setting to
conform to the numerical convention in many countries. This
procedure ([ON]/[:])) will reverse the current setting:
1. Turn off the calculator.
2. Press and hold [ON].
3. Press and hold[].
4. Release[ON], then release[-].