RPN-25 CE

New and changed instructions allow you to handle up to 13 statistics data blocks of 7 registers each in parallel.

• ∑REG nn
Sets the first register of the current statistics block to Rnn (R00 to R93).

• ∑REG?
Returns the register number nn of the current statistics data block.

• ∑REGSTD
Sets the first register of the current statistics data block to the default value (R03).

• ∑SWAP41
Swaps the current statistics data block with the block at the HP-41 standard location (R11 to R16).

• ∑SWAP32 (renamed from SWAP∑)
Swaps the current statistics data block with the block at the HP-32 standard location (R10 to R15).

Bug fix: If the buttons "Delete" and "Import" were grayed out in the program file list, selecting a program would not enable them.

• Internal optimizations and cleanups.

• Modified Info screen to avoid clipping by the Dynamic Island.

• Call up details of Extra Functions directly from the app (via Safari)

• Improved LCM and GCD functions can handle up to 4 arguments

• Vintage Mode:
– No RCL register arithmetic
- No dotted register names, e.g. "R.5"
– No access to registers R8 and R9
– Program execution speed comparable to real HP-25
– The vintage mode setting is stored along with the program

• Runs on Apple Silicon Macs (see notes on homepage cuveesoft.ch)

• RPN-25 CE requires iOS 12.0 or later

• Bug Fixes:
– Instructions GET SEPS and HAPTICS? now work correctly in interactive mode.
- Executing the CLOCK command when the clock was already running would not clear the AM/PM indicator.

• Trigonometric mode indicators:
DEG, RAD, and GRD indicators are never shown in vintage mode.
In normal mode, the default setting DEG appears only on the high-contrast display.

• Obsolete mode changes involving "magic numbers" 19390104 and 19390105 have been removed.

• Fixed issues involving the R/S key.

• Added a switch in Settings to set the calculator to vintage mode, simulating a real HP-25.

• If RPN-25 is set to vintage mode, shifted functions not available on a real HP-25 are not presented anymore.

• In RUN mode, holding SST or BST keys depressed now shows the current or previous instruction code, respectively, just like on a real HP-25.

• The DOW (Day of week) function doesn't require the display to be set to FIX 6 or higher anymore in interactive mode.

• If auto-running of a program is disabled (by setting flag 99), it may be re-enabled by saving Settings with Auto-Start set to ON (in addition to clearing flag 99 or turning power off and on.)

• Decimal point and thousands separator symbols are now set according to the iOS locale.

• In addition to sliding, the power switch may also be moved by double-tapping. A single-tap is ignored when the calculator is on.

• Clock display (f- or g-PRGM/RUN) now shows the date in high-contrast mode.

• New instructions:

- HAPTIC f sets the haptic level of the iPhone to level f (1…3, 0 for no haptics)
- HAPTIC? returns the current haptic level (0…3)

„Sounds & Haptics“ / „System Haptics“ must be on in the iPhone's settings.


Bug Fix

• Issues with DOW function. Now works correctly for all Gregorian dates (Oct 15, 1582 and later.)

• If high-contrast display is on, the mantissa of a number (g MANT) is now shown without thousands separators.

• Also in high-contrast mode, the DOW (day-of-the-week) function now shows the date as text, in addition to the day number.

• Pressing a User Key now clears any user message, just like pressing a regular key does.

• Added stack indirection (by prefixing stack register name with "i") when specifying values to show in MSG, MSGP, MSGS instructions.

• Numeric values in MSG, MSGP, MSGS instructions may now be forced to the FIX 0 format (by prefixing their name with "I").

• New instructions:
- FLOOR rounds down towards negative infinity.
- CEIL rounds up towards positive infinity.
– "BASE? b" (b = 2..9) tests if the positive integer part of X is a valid number in base b. If not, the next step is skipped.
– CF0to9 clears the flags F0 to F9.
– HIDE 41 and SHOW 41 controls the visibility of the flag 41 indicator.
- Convert between units of power (kW, mechanical horsepower hp, metric horsepower PS)


New Sample Programs:

• CODATA 2018
Allows easy access to 354 physical constants, along with their names. Easily adaptable for your own lookup tables.

• Boolean Functions and Base Conversions
AND / OR / XOR / NOT operations and conversions from any base to any other (base = 2 to 10)

• Mixing
Mix cold and hot liquids to obtain a specific amount of liquid at a specific intermediate temperature.



Bug Fixes

• Copy/paste in PRGM mode didn't work if high-contrast mode was turned on.

• Fixed issues with wrapping/unwrapping number literals followed by a CHS instruction.

• The sequence of digits defining a number with an exponent that is a multiple of 10 did not correctly translate into a literal.

• Added large-digits, LCD-like high-contrast display option (triple-tap display to turn on and off).

• Nicer looking clock display with colons. To turn on, tap f or g, then tap the PRGM/RUN switch.

• New or changed instructions:

- HC DSP sets high-contrast display if x ≠ 0, standard LED display if x = 0.
- GET SEPS returns the thousands separators setting: 0 = OFF, 1 = ON
- SET SEPS sets the thousands separators setting: 0 = OFF, other = ON
- SPEC DSP displays up to 25 special characters in high-contrast mode
- CLOCK shows or hides the 12- or 24-hr real-time clock
- DATE shows clear-text weekday and date if high-contrast display is on

• Quick Access to LBL, USR, and GTO/GSB
Tap the LG button in the program list view to quickly see all labels and User Keys in your program.
Double-tap LG to see all branches to labels.
Sort by step or item.
Double-tap an item to select the corresponding program step.

• User Keys may now have leading blanks

• Suppress Auto-Start of a program by setting flag 99 before importing

• New instructions:
- BACK s Go back s steps (s = 1..9)
- DEL Y Remove y, drop stack
- DEL Z Remove z, copy t to Z
- Y→ZT Copy y to Z and T
- Y→T Copy y to T
- Z→T Copy z to T
- PRGM Switch to PRGM mode

• New Sample Programs:
- 41-Terrestrial Geodetic Distance•
- 41-Giant Planets 2022•
- NPV & IRR• (for up to 92 cash flows)
- Solve for f/x)=0 Newton• (now with User Keys)


Bug Fixes

• Stopped instruction name from appearing below display when it shouldn't.

• Fixed display issues when running on an iPod touch

• Fixed instruction name SPEC VIS showing as SPEC DSP

• MSG, MSGP, MSGS can show stack and register values below the display

• In the program listing, double-tap a USR instruction to quickly find its corresponding LBL (and vice versa)

• Change the program listing font with a simple tap on the new button "F"

• All of the flags F0 to F9 may now appear in the display, if set.

• When an error occurs, the stack display is automatically turned off.

• New instructions:
- P→S copies primary registers R0..R9 to secondary registers R.0..R.9 (R10..R19)
- SHOW STK and HIDE STK control the visibility of the stack in the display area
- SPEC DSP creates special displays, i.e. blank, all "-", or all "o"
- STEP VIS controls the visibility and mode of the program step indicator below the display
- FLAG VIS controls the appearance of flags F0 to F9 in the display

• Apply a filter to quickly find any program.

• Sample Programs may be hidden in the list of programs.

• New Sample Programs:
- _Demo 25• (showcases new features)
– Cost and Price Computations•
– 41-Sudoku Solver
– 41-Sudoku Puzzles
- 41-Discriminant of a Polynomial•
- 41-Garden-Hose Method•

• Sample Programs featuring User Keys are now identified by a trailing dot (•)


Bug Fixes

• User Keys were not responsive while the display showed the stack.

• In the program listing, wrapping a multi-step number like ". 0 0 5" into a single step would drop the mantissa.

• Program comment lines would behave oddly in some situations.

• Programs containing foreign characters in their name would not be auto-selected in the list of programs.

• Introducing: User Keys
Enjoy the luxury of assignable user keys! Well-known as keys A through E from calculators like HP-65 and HP-67, these keys call subroutines in the user's program.

On RPN-25 CE, they come with a few twists:
- 5 key locations, positioned directly above the display
- Up to 15 keys when using f and g modifiers
- Each key may have a legend (1 to 6 characters)
- Unnamed keys, or keys named with a single underscore, are ignored.
- The legend and the operation associated with each key may be changed anytime, even by a running program.
- Direct and indirect subroutine calls

Check out the tutorial on the RPN-25 CE website!


• New Programs: TVM - Time Value of Money
- TVM 2d and TVM 2i demonstrate the use of user-defined keys.
- TVM 14B simulates a number of functions of the HP-14B Business Calculator.
(Make sure to add the new programs in the program file list.)

• New Setting: "Auto-Start on Program Loading"
- A program saved with the setting Auto-Start turned on will automatically run after loading.
- Perfect for setting up User Keys.



Bug Fixes

• Suppressed illegal key pairs: STO/RCL/GTO followed by EEX or R/S.
• The program step display is now turned off if power is off.
• If turned off, the program step display will not reappear on switching from PRGM mode to RUN mode.
• Pasting a program larger than 100 steps into the display in 99-step mode would cause a crash.

• Data Files: Load register data from files without disrupting the currently loaded program.

• New sample program: "Travelling Salesman"; demonstrates the use of data files.

• New functions: LambertW and LambertV (see website)

• New functions STO YZT, RCL YZT
Store and recall stack registers Y, Z and T. Useful for doing a calculation on the value in X without affecting the other stack registers.

• New comparisons: x≈y and x≈0 ("almost equal"). Execute next step if x is closer to y or 0 than 2E-9, otherwise skip next step.

• New instruction: CLRX. Executes CLX without disabling automatic stack lift.

• New sample programs: "Interest Amount & PMT" and "Discrete Fourier Transform"


Bug fix:

• Pasting a text listing, e.g. from Mail, into the display would fail on certain instructions.

• The Julian Date conversion JDN now accepts a time value in Y. Invalid values for date and time are replaced by the current date and/or time. A negative date is treated as Julian, otherwise Gregorian.

• If vintage mode is turned on, NOP instructions that are targets of branch instructions are not automatically converted into LBL instructions.


Bug fix:

• Inserting a MSG instruction would cause a crash

** 10 YEARS of CUVEE SOFTWARE SIMULATORS **

This is a big update of RPN-25 CE, celebrating the 10th anniversary of RPN-45 HD, the first in a series of simulators of famous HP calculators.

• 3.0.1: Fixes crash in PRGM mode when a GTO instruction addressed a step beyond the used program area.


• Now with symbolic labels 00..99 not tied to program step numbers!
Use the new _LBL, _GTO and _GSB instructions along with the regular GTO and GSB.

• Program memory can be allocated as either 99 steps or 999 steps (select in Settings)

• Single-step constants: to create, double-tap the first step of a multi-step constant definition.
Double-tap the constant to revert to the editable multi-step representation.

• User messages: display any message (up to 30 characters) right below the display. Optionally execute PAUSE automatically before the program continues, allowing the user to enter a value. Or stop program execution.

• Program comments: use any step to display free text in the program listing.
(Load program "41-Polynomials" to see an example.)

• Indirect branching to symbolic label stored in any stack or regular register

• Overflow on ∑+ and ∑- operations is now handled like on a real HP-25 (in vintage mode). Setting flag 41 simulates the HP-41's behavior, i.e. no program abort on overflow of a register.

• New instructions:
MSG, MSGP, MSGS: show user message below display
// text: add program comments
SKIP: skip the next 0 to 9 steps
GETPSE, SETPSE: read and set the PAUSE setting
END stops program execution w/o returning to step 0
JND returns the Julian day number of a date
DY2000 returns the number of days between a date and Jan 1, 2000
SND nn plays sound number nn (0..99)
ROUND n rounds x to n fractional digits (0..9)
DELAY: same as PAUSE but without flashing "PAUSE"
NUM2DIGS nn: decompose 10-digit mantissa into single digits at Rnn..Rnn+9
DIGS2NUM nn: create number from 10 digits stored in Rnn..Rnn+9
ISGi, DSEi: indirect versions of ISG and DSE
SFi N, CFi N, FS?i N: handle flags indirectly via stack register
ST41, RC41: store and recall the flag 41 status
x³ returns the cube of x
y^x{0} is the same as y^x, except that 0⁰ = 1

• Renamed INCR and DECR to x+1 and x-1.

• Long-press step number to show/hide the previously executed step.

• Entering a numeric value while a PAUSE is in effect restarts the pause with each keypress.

• New sample programs, most of them using symbolic labels:
- "41-Conics"
- "41-Stirling Numbers"
- "41-Stirling Numbers generalized"
- "41-Ramanujan Tau Numbers"
- "41-Multinomial Coefficients"
- "41-Fibonacci, Tri-, Tetra-, k-nacci"
- "41-Fibonacci Multiprecision"
- "41-Apéry's Numbers"
- "41-Cyclic Universe 1a, Radiation only"
- "41-Cyclic Universe 1b, Radiation only"
- "41-Gauss-Legendre 4-point"
- "41-Diff. Equations 2nd Order"
- "41-Weierstrass-Durand-Kerner"
- "41-Norm of a Matrix"
- "41-Integral over a Sphere"
- "41-Arc Length of Parametric Curve"
- "41-Delta T (∆T)"
- "41-Giant Planets 2021"
- "41-Debye Function"
- "41-Multiple Series"
- "41-Successive Approximation"
- "41-Euler Transformation"
- "41-Illuminated Fraction of Moon"
- "41-NumInt - Double Exponential"
- "41-Euler-Lagrange Equation"
- "41-Downhill Simplex Method"
- "41-Illuminated Fraction of Moon"
- "41-Polynomials" (646 steps)
- "41-Vector Calculus Curl, Div, Grad, Lapl"
- "41-Anchorage Knik Arm" (861 steps)
- "41-Equilateral Triangle Puzzle"
- "TVM - Time Value of Money"
- "Dial"

• Set flags 0…3 and 41 show on the display (F3 only if F41 is set.)

• Storing 19390105 in register R0 turns vintage mode off

• Refined RTN instruction: in a running program without return address, program execution stops. In interactive mode, a branch to step 0 is executed.

• To turn the calculator off, swipe the power button left; tapping is not enough.



Bug fixes:

• TIME did not lift the stack
• GTO 78 would incorrectly show as GTOc_COS

** 10 YEARS of CUVEE SOFTWARE SIMULATORS **

This is a big update of RPN-25 CE, celebrating the 10th anniversary of RPN-45 HD, the first in the RPN series of simulators of famous HP calculators.


• Now with symbolic labels 00..99 not tied to program step numbers!
Use them with corresponding _LBL, _GTO and _GSB instructions.
(The original implementation with step numbers is still available, of course.)

• Program memory can be allocated as either 99 steps or 999 steps (select in Settings)

• Single-step constants: to create, double-tap the first step of a multi-step constant definition.
Double-tap the constant to revert to the editable multi-step representation.

• User messages: display any message (up to 30 characters) right below the display. Optionally execute PAUSE automatically before the program continues, allowing the user to enter a value. Or stop program execution.

• Program comments: use any step to display free text in the program listing.
(Load program "41-Polynomials" to see an example.)

• Indirect branching to symbolic label stored in any stack or regular register

• Overflow on ∑+ and ∑- operations is now handled like on a real HP-25 (in vintage mode). Setting flag 41 simulates the HP-41's behavior, i.e. no program abort on overflow of a register.

• New instructions:
MSG, MSGP, MSGS: show user message below display
// text: A step that contains only "text" without affecting the program in any way
SKIP lets you skip the next 0 to 9 steps
GETPSE, SETPSE: read and set the PAUSE setting
END stops program execution without returning to step 0
JND returns the Julian day number of a date
DY2000 returns the number of days between a date and Jan 1, 2000
SND nn plays sound number nn (0..99)
ROUND n rounds x to n fractional digits (0..9)
DELAY is the same as PAUSE but without flashing "PAUSE"
NUM2DIGS nn decomposes the 10-digit mantissa into single digits stored at Rnn..Rnn+9
DIGS2NUM nn creates number from the 10 digits stored in Rnn..Rnn+9
ISGi, DSEi: indirect versions of ISG and DSE
SFi N, CFi N, FS?i N: handle flags indirectly via any stack register
ST41, RC41: store and recall the flag 41 status
x³ returns the cube of x
y^x{0} is the same as y^x, except that 0⁰ = 1

• Renamed INCR and DECR to x+1 and x-1, respectively.

• Long-press step number to show/hide the previously executed step.

• Entering a numeric value while a PAUSE is in effect restarts the pause with each keypress.

• New sample programs, most of them using symbolic labels:
- "41-Conics"
- "41-Stirling Numbers"
- "41-Stirling Numbers generalized"
- "41-Ramanujan Tau Numbers"
- "41-Multinomial Coefficients"
- "41-Fibonacci, Tri-, Tetra-, k-nacci"
- "41-Fibonacci Multiprecision"
- "41-Apéry's Numbers"
- "41-Cyclic Universe 1a, Radiation only"
- "41-Cyclic Universe 1b, Radiation only"
- "41-Gauss-Legendre 4-point"
- "41-Diff. Equations 2nd Order"
- "41-Weierstrass-Durand-Kerner"
- "41-Norm of a Matrix"
- "41-Integral over a Sphere"
- "41-Arc Length of Parametric Curve"
- "41-Delta T (∆T)" (343 steps)
- "41-Giant Planets 2021"
- "41-Debye Function"
- "41-Multiple Series"
- "41-Successive Approximation"
- "41-Euler Transformation"
- "41-Illuminated Fraction of Moon"
- "41-NumInt - Double Exponential" (347 steps)
- "41-Euler-Lagrange Equation" (347 steps)
- "41-Downhill Simplex Method" (465 steps)
- "41-Illuminated Fraction of Moon"
- "41-Polynomials" (646 steps)
- "41-Vector Calculus Curl, Div, Grad, Lapl" (627 steps)
- "41-Anchorage Knik Arm" (861 steps)
- "41-Equilateral Triangle Puzzle"
- "TVM - Time Value of Money"
- "Dial"

• Flags 0…3 and 41 are shown on the display if set (F3 only if F41 is set.)

• Storing 19390105 in register R0 turns vintage mode off

• To turn the calculator off, swipe the power button left. Simply tapping it doesn't suffice anymore.


Bug fixes:

• TIME did not lift the stack
• GTO 78 would incorrectly show as GTOc_COS

• Execute Extra Functions in RUN mode

• VIEW instruction
While a program is running, watch any stack or memory register without affecting the calculation in any way. A memory register may even be indirectly addressed by any stack register. Execute CLD, or tap the display to restore the normal view.

• CLD instruction
Restores normal display after a VIEW instruction

• DSMSTO and DSMRCL instructions
Store and recall display settings

• REGSET sets any range of registers to a value

• REGSORT sorts any range of registers

• xi≷yi swaps registers defined in X and Y

• 100 flags (up from 10.) Their states are shown in extended register view.

• Flags 24 and 25 may be used to handle errors (like on the HP-41)

• Flag 41 simplifies running HP-41 programs on RPN-25

• Additional flag instructions:
- FC? nn: tests if flag nn is cleared
- FC?S nn: tests if flag nn is cleared, then sets it
- FS?C nn: tests if flag nn is set, the clears it
- STFLAGS, RCFLAGS: store/recall groups of 32 flags
- CFInd, SFInd: address flags directly or indirectly
- TOGFLG nn: toggle flag nn

• More comparison instructions:
- x#NN: six comparisons between x and any register defined in Y
- x#nn: three comparisons between x and register nn

• Date functions:
- DATE: current date as mm.ddyyy
- DATE+: date y + x days. Easter date if y = 0 and x ≥ 1583.
- ∆DAYS: number of days from date y to date x.
- DOW: day of the week, day number, week number
- MDY→YMD, YMD→DMY, DMY→MDY, etc. (date format conversions)

• Instruction FILL RAN# now accepts a user-defined range

• Indirect register addressing ignores sign and fractional part of the argument

• Mathematical and physical constants (CODATA 2018-compliant)

• When executed interactively, ISG and DSE do not change the program counter anymore.

• In vintage mode, ISG, DSE, RND, RAND, and CLEAR ∑ are not shown and are not functional.

• UI change: double-tap display for Extra Functions, triple-tap for Settings

• Sample programs:
- "41-Extrema" (new)
- "41-Parabolic Interpolation" (new)
- "41-Infinite Nested Radicals" (new)
- "41-Large Factorials" (new)
- "41-Multi- and Hyperfactorials" (new)
- "41-Factorial Digits" (new)
- "41-Kaprekar Series" (new)
- "41-Golomb Sequence" (new)
- "41-Euler Numbers 1" (new)
- "41-Euler Numbers 2" (new)
- "41-Harmonic Numbers" (new)
- "41-Pell's Equation" (new)
- "41-Kepler's Equation" (new)
- "41-Easter Date" (new)
- "41-Equilateral Triangle Puzzle" (new)
- "41-Multivariate Gamma, Digamma" (new)
- "41-Loxodromics" (new)
- "41-Geodesic Distance" (new)
- "41-Square Root modulo m" (new)
- "41-Unrestricted Partitions" (new)
- "41-Permutations" (new)
- "Amortization" (revised)
- "TVM - Time Value of Money" (revised)


Bug fixes:

• Deleting a block of program steps could result in wrongly adjusted branch targets in some cases

• Pasting non-XML program text could corrupt instructions with single-digit opcodes

• ISG/DSE commands were susceptible to internal rounding effects

• Now with 100 registers (R00..R99) !

• New register view showing all 100 registers

• Print (or mail as PDF) the program or its description

• Define register arguments without leaving the Extra Functions list

• Store/recall arithmetic between X and any stack register

• Store/recall arithmetic between X and any register addressed by any stack register

• New functions and operations:
STO[op]nn, RCL[op]nn: register arithmetic between x and register nn (00..99)
STi[op]nn, RCi[op]nn: register arithmetic between x and the register defined in register nn
xi≷ nn: swap x with register defined in register nn
STO[op]N, RCL[op]N: stack register arithmetic between x and stack register N
STi[op]N, RCi[op]N: register arithmetic between x and the register defined in stack register N
x≷ N: swap x with stack register N
xi≷ N: swap x with the register nn defined in stack register N
ISG nn, DSE nn: increment/decrement register nn and skip if condition met
ISG N, DSE N: increment/decrement stack register N and skip if condition met
ISGi N, DSEi N: increment/decrement register nn defined in stack register N and skip if condition met
SND nn: play sound defined by value in register nn
CLR ALL: clear all registers
CLR EXT: clear extended registers R20..R99
CLRGX: clear a range of registers with optional increment
REGCOPY: copy a range of registers to a different location
REGSWAP: swap the contents of two ranges of registers
REGS ALL: show all registers R00..R99
SIGN: return -1, 0, or +1 if x is negative, positive, or zero
PRIME?: set flag 0 if x is prime
ERF/ERFC: Gauss error function and complementary error function
MATH: BesselJ, BesselY, Bernoulli, Zeta
ERROR nn: replaces the previous ERROR 1 and ERROR 2 functions.
The new version supports various boiler-plate messages.

• Optional vintage features
- Send 19390104 to register 0 to toggle some features on and off:
- New program step replaces the next step instead of being inserted
- ISG, RND and CLEAR ∑ labels are hidden (but still functional)

• A program running longer than one minute will emit a short beep when executing the final GTO 00 command

• Tap f or g, then the PRGM/RUN switch to see a 12- or 24-hour clock.

• Improved accuracy in extreme cases of y^x with positive, integer x.
For example, 1.0000001^(2^27) = 674530.4707, not 674530.4760

• Double-tapping "Continuous Memory" doesn't show the Info screen anymore.
Use the info button instead.

• Call up "What's New" anytime from Info screen

• New sample programs:
"Amortization"
"Bell Numbers Advanced"
"Decimals of e"
"Decimals of Pi"
"Multi Curve Fitting"
"NPV and IRR"
"Square Roots & Integer Powers"
"TVM - Time Value of Money"


Bug fixes:

• Fixed display issues when using the iPhone in "Zoomed" mode

• The RND function didn't work correctly in regions using a comma as decimal point

• Double- or triple-tapping the empty program listing could cause a crash

• Setting the haptic feedback level didn't check sufficiently for the correct code

• More than 80 new Extra Functions added!

• Inserting extra functions is now an easy 2-step process:
1. Triple-tap the display in PRGM mode
2. Double-tap the desired function

• Some programs have been added or updated. Be sure to execute "Reload Sample Programs" to refresh the list.


Bug fix:

• The thousand's separator setting returned to the default value (ON) after restarting the app.