# HP-45

Type HP-45Advanced Scientific Electronic Pocket Calculator. Scientific 1973 1976 RPN Red LED seven-segment display 15 digits (decimal point uses one digit), (±10±99) Four-register operational stack with nine memory registers + LASTx register Internal rechargeable battery or 115/230 V AC, 5 W Calculator: 9 oz (255 g),recharger: 5 oz (140 g) Length: 5.8 in (147 mm),width: 3.2 in (81 mm),height: 0.7 in (18 mm) – 1.3 in (33 mm)

The HP-45 was the second scientific pocket calculator introduced by Hewlett-Packard, adding to the features of the HP-35. It was introduced in 1973[1] with an MSRP of \$395[2] (equivalent to \$2,229 in 2018).[3] Especially noteworthy was its pioneering addition of a shift key that gave other keys alternate functions.

The calculator was code-named Wizard,[4] which is the first known use of a code name for a calculator.
It also contained an Easter egg that allowed users to access a not-especially accurate stopwatch mode.[5] An accurate version of the stopwatch mode was officially featured in the 1975 successor of the HP-45, the HP-55.

The display of the HP-45 hidden timer showing 00 hours 00 minutes 07 seconds and 58/100 second.

HP-45 functions
Arithmetic +, −, ×, ÷
Trigonometry sin, arc sin; cos, arc cos; tan, arc tan (decimal degrees, radians or grads).
Logarithms log10x, 10x; logex, ex
Rectangular coordinates ↔ polar coordinates.
Conversion units: cm/in, kg/lb, ltr/gal
Other 1/x, √x, x2, yx, n!, %, Δ%, π, vector arithmetic, register arithmetic.
Statistical accumulation with mean and standard deviation calculations.
Fixed point and scientific display modes, 0 – 9 decimal places round-off.

## Emulators

Several individuals and companies make software emulators of the HP 45 series calculators.

Nonpareil, high-fidelity simulator for calculators
Emulates, among other, the HP-45. Licensed under the GNU General Public License (GPL). Available for Microsoft Windows.
HP-45 Emulator
HP-45 Emulator written in Java. Licensed under the GPL 3. Available for Android [6] and Symbian.[7]
HP-45 Windows Phone 7 App
An Emulator for Windows Phone 7.
HP-45 Emulator in JavaScript
The HP-45 Program ROM was translated to JavaScript to have an exact simulation of the original calculator for use in web browsers.

## References

1. ^ "HP Virtual Museum: Hewlett-Packard-45 advanced scientific pocket calculator, 1973". Retrieved 2017-10-15.
2. ^ Free, John R. (April 1974). "Those incredible new scientific pocket calculators". Popular Science. p. 124. Retrieved 2017-10-15.
3. ^ Federal Reserve Bank of Minneapolis Community Development Project. "Consumer Price Index (estimate) 1800–". Federal Reserve Bank of Minneapolis. Retrieved January 2, 2019.
4. ^ HP Calculator History – The HP-45
5. ^ HP-45 Calculator as a Stopwatch
6. ^ Android
7. ^ Symbian