The Museum of HP Calculators


HP-9805 Features

Features in optional ROMs are listed as Option.
Features in HP mag card or tape Application Pacs are listed as +.
Other software is not included.
Display and Keyboard HP-9805
Display type Optional LED
Display format 1 Line
FIXed number format Yes
SCIentific number format Yes
ENGineering number format -
STanDard / ALL number format -
Alpha messages and prompts -
Softkeys labeled by mag. card or overlay -
Softkeys labeled by display menus -
Softkeys with neither labeling system -
Status annunciators -
Redefinable keyboard Partial*
Logic HP-9805
Logic system Algebraic
Stack levels -
Last x -
Undo -
Precedence -
Parentheses Yes
Storage Addition (STO +) -
Storage Arithmetic (STO +, −, ×, ÷) -
Storage Exponentiation (STO ^) -
Recall Arithmetic -
Named variables -
Multiple data types -
Directories -
Math HP-9805
+, −, ×, ÷ Yes 
1/x Yes
Yes
x2 Yes
LOG x Yes
10x -
LN x Yes
ex Yes
yx Yes
π -
% Yes
% change -
INTeger truncation and ABSolute value -
Trigonometric functions (SIN, COS etc.) -
Hyperbolic trig. (SINH, COSH etc.) -
# of trig. modes (degrees, radians, grads) -
Advanced Math HP-9805
Solver / root finder -
Numeric integration -
Complex numbers -
Matrix operations -
Matrix writer -
Equation writer -
Symbolic operations -
Fractions -
Plotting and graphics (display) -
Plotting and graphics (printer / plotter) Yes
Statistical HP-9805
Mean, standard deviation (# of variables) 2
Σ of n, x, x2 Yes
Σ of n, x, x2, y Yes
Σ of n, x, x2, y, xy Yes
Σ of n, x, x2, y, y2, xy Yes
Σ of lists -
Random number generator -
Linear regression, estimate  Yes
Curve fitting Yes/Option
Correlation coefficient -
Normal distribution -
Factorial -
Gamma -
Combinations and permutations -
Scientific and Time HP-9805
Polar / rectangular conversions Yes
Base conversions (2, 8, 10, 16) -
Arithmetic in bases 2, 8 and 16 -
Bit operations (AND, OR, XOR, ...) -
Selectable word size (1-64 bits) -
Selectable complement mode (1's, 2's, unsigned) -
Decimal hrs / hrs.min.sec. conversions Yes
Hrs.min.sec arithmetic -
Time of day clock -
Timer -
Dynamic calculations (timer × rate) -
Alarms -
Unit Conversions HP-9805
Centimeters / inches -
Millimeters / inches -
Meters / feet -
Kilograms / pounds (mass) -
Newtons / pounds (force) -
British thermal units / joules -
Liters / gallons -
° Celsius / ° Fahrenheit -
Other -
User-defined units -
Time Value of Money HP-9805
Number of payments (n) -
Interest rate (i) -
Present Value (PV) -
Payment (PMT) -
Future Value (FV) -
Cash Flow Analysis HP-9805
Net present value (NPV) -
Internal rate of return (IRR) -
Amortization HP-9805
Accumulated Interest (ACC INT) -
Balance (BAL) -
Depreciation HP-9805
Straight line (SL) -
Sum of the years digits (SOYD) -
Declining balance (DB) -
Bonds and calendar functions HP-9805
Bond price -
Bond yield -
Date arithmetic / calendar functions -
Memory and Programming HP-9805
Programming language(s) -
RAM / Max # of variables or addressable registers 1 + 17 stat
Registers
Max # of program steps -
RAM / Max vars or regs with full optional RAM 30 + 17 stat
Registers
Max # of prog steps with full optional RAM -
Merged program steps  -
Manual register / program memory allocation  -
Automatic register / program memory allocation -
Overlapped register and program memory -
Continuous memory -
Flags -
Conditional tests -
Subroutine levels -
Indexed looping (increment by +/- 1, end at 0) -
Indexed looping (choice of increment and end) -
Multiple index / loop registers -
Line number addressing -
Branching by relative line number -
Global program label addressing -
Local program label addressing -
Indirect / computed addressing and control -
Multiple indirection registers -
Pause -
Alpha messages and prompts in programs -
Alpha program listings -
Alpha string manipulation -
Program step insert / delete -
I/O and Expansion Features HP-9805
ROM modules Yes
RAM modules or expansion option -
General expansion slots / connector -
Magnetic card reader/writer -
Tape drive -
Disk drive -
Upgradeable firmware -
Optical wand -
Serial port -
Infrared input -
Infrared output -
Printer Yes
Networking -
Other -
General HP-9805
Sounds -
Self test -
Hard case (in addition to soft case) -
Additional Features Histogram
÷ by 12
Auto decimal
Batteries -
Length (inches) 15.4"
Width 10.0"
Height 5.6"
Weight (oz or lbs) 13.2 lbs
Year of introduction 1973
Features in optional ROMs are listed as Option.
Features in HP mag card or tape Application Pacs are listed as +.
Other software is not included.

Unlim means limited only by available memory.
HP-9805 notes:
  • FIXed mode set by Rnd () #. SCIentific mode set by Rnd () . #.
  • The block of 15 keys at the left were part of the ROM pack.
  • Came with a printer standard and the display was optional.
  • Expanded Stat option also added 29 numbered registers.

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