RPN-45 HD 6.5 - App Store

RPN-45 HD version 6.5

Updated At: 2026-06-21

Changes: Version History Improved compatibility with real HP-45 when using D.MS conversions: – With „Super-45" set to off: same results as real HP-45 – With "Super-45" set to on: improved results (no digits dropped by conversion) EXAMPLE Convert 12.345612: – "Super-45" off: D.MS-> 12.58225556, then -> D.MS back to 12.34560000 – "Super-45" on: D.MS-> 12.58225556, then -> D.MS back to 12.34561200 6.5 Mar 9 Various cleanups 6.4 07/28/2025 • Faster startup – no delay until the first button press is recognized after switching on. 6.3 05/10/2025 • In "Super-45" mode, results such as 9.99×10⁹⁹ now appear correctly rounded both in the display and on the printer for all decimal point settings, e.g. SCI 1 (in contrast to the original HP-45). • Certain calculations, e.g. 100⁷⁵, caused the app to crash. Version 6.2.1 avoids a possible crash when the calculator is not set to "Super-45" mode. 6.2.1 03/10/2025 • In "Super-45" mode, results such as 9.99×10⁹⁹ now appear correctly rounded both in the display and on the printer for all decimal point settings, e.g. SCI 1 (in contrast to the original HP-45). • Certain calculations, e.g. 100⁷⁵, caused the app to crash. 6.2 03/03/2025 • Disabled low-battery indicator (all decimal points lit) when running on Apple Silicon Mac. 6.1 11/06/2024 • Changed gestures on the "Quick Reference Guide": - Tap to show info screen - Double-tap to show registers - Removed the swipe-up gesture • Thousand separators are now supported in Large Display Digits mode. • In addition to using the Settings, you can toggle Large Display Digits by tapping the gold key, then double-tapping the display. • In addition to "FIX .", thousand separators may be toggled by tapping the gold key, then triple-tapping the display. 6.0 07/05/2024 • Runs on Apple Silicon Macs (see notes on homepage cuveesoft.ch) • RPN-45 HD requires iOS 12.0 or later 5.7 12/23/2023 • Key flashing may be turned on or off in Settings. 5.6 05/12/2023 • Improved handling of thousands separators Bug Fix: • When using an external keyboard, some keys were unresponsive in iOS 15. 5.5.5 06/05/2022 • Improved calendar calculations: - Date range is Jan 1, 0001 to Dec 31, 9999. - For any date, the day-of-the-week is shown fully spelled out. - Enter a date as mm.ddyyyy (US, Canada) or dd.mmyyyy (elsewhere), then execute DATE. - A positive input is interpreted as Gregorian, a negative input as Julian. - Convert any date from Gregorian to Julian (and vice versa) by executing DATE. - Enter an integer n, execute DATE to see the date n days later or earlier than the date in Y. If the date in Y is invalid, the last valid date is used. (The current date, if none is available.) Y shows the Julian Day Number of the displayed date. - If Y = 0: 0 DATE returns the current date. n DATE returns the Easter date of the year n (n = 1583 to 4099). j DATE returns the date corresponding to the Julian Day Number j (Gregorian if j is positive, Julian otherwise; j = 1,721,424 to 5,373,484) - Execute ∆DYS to get the number of days from date Y to date X. Y shows the result based on the 30 days/month calendar. Bug Fix: • Stack values didn't show correctly in the register view popup in portrait mode 5.5 02/16/2022 • iPad mini (2021) compatibility 5.4.2 10/03/2021 • Suppressed clipboard notification on each keypress (iOS 14) Bug Fix: • An empty clipboard could cause a crash on startup (iOS 14) 5.4.1 04/15/2021 • Improved accuracy in extreme cases of y^x with positive, integer x. For example, 1.0000001^(2^27) = 674530.4707, not 674530.4760 Bug Fixes: • Fixed an occasional issue causing mail dialog to close prematurely • The RND function didn't work correctly in regions using a comma as decimal point 5.4 11/05/2020 • New function ABS (purple-6). Mainly useful with complex numbers. • New or changed commands for external keyboard: - shift-cmd-S: thousand's separators on/off - > : swaps registers R0…R9 and R.0…R.9 – cmd-P: shows or hides printer - option-delete: CLR A (clear stack and all registers) – option-L: LAST x (was cmd-L) – control-1/2/3: set ribbon color to black/blue/green - shift-control-option-S: backup registers - shift-control-option-R: recall registers from backup - shift-control-option-[less than]: exchange registers with backup Download the complete list from the cuveesoft.ch homepage. • Press shift-control-option-N to turn on the calculator, clear registers and stack, set FIX 2 mode, set DEG mode and hide the stack display. 5.3 06/30/2020 • Additional commands for external keyboard: – shift-K: stack display – option-P: π - control-$: ∑- Download the complete list from the cuveesoft.ch homepage. Bug fix: • Ending timer mode using the ENTER didn't restore the decimal key legend 5.2.1 04/08/2020 • Additional commands for external keyboard: – shift-F: selects purple key functions (same as pressing gold key twice) – N: executes n! – D: executes ∆% (percent difference) • Simplified installation of user background image via Files app (see built-in Info, "Settings") • Key flashing may be turned off and on: - Store 19390101 in R1 to turn off - Recall 19390101 from R1 to turn on (Hewlett-Packard Company was founded on Jan 1, 1939) • In TRACE mode, the Easter date function is now clearly marked. (Reminder: set y = 0, x = desired year (1583–4099), and execute DATE.) Bug fixes: • "Roll down" key didn't show the correct arrow in all cases • Some keys used in timer modes didn't show their key-down image • External keyboard command "s" (STO) was inoperational 5.2 04/01/2020 • Hardware keyboard support! Use your iPad's Smart Keyboard, or any Bluetooth keyboard, to do calculations, change views, adjust settings, control the printer, and more – without ever touching the iPad screen. Press and hold the cmd-key to see the most important commands. Type cmd-? to see which key does what. • HYP mode may be cancelled by pressing the EEX key again • Printer mode ALL is now called TRACE • Portrait mode is back again! Bug fixes: • Gold key + EEX was logged as GRD instead of HYP • Logging chess moves would print out unneeded lines • Move count of chess player 2 would not be updated in portrait mode register view • Using scientific notation could crash the app in some regions, i.e. Australia, Sweden, Slovenia. 5.1 03/17/2020 • Stack display: LastX may be shown or hidden independently from other stack registers. Simply tap on their respective areas. • Dark Mode compatibility • The rarely used portrait mode has been dropped Bug fixes: • Overflow value now shows correctly in SCI/ENG display modes • Executing the summation command ∑ with a very large argument would cause a crash • Calling up and saving settings while entering a number with an exponent would cause a crash on the next digit input • The operation FIX 0 was logged on the printer as "FIX S" instead of "FIX 0" RPN-45 HD now requires iOS 11 or later. 5.0 01/25/2020 • Print commands now work like on the iPhone version. You can print the display value, the stack, the registers, or a blank line - even rip off the paper tape - directly from the keyboard after tapping the gold key once or twice. Multiple blank lines are created automatically by holding the key down. • Printing the display value while entering a number always prints in grey color • Roll-up stack: tap gold key twice, then tap Roll-down • Statistics register names (shown by long-pressing the register window) are suppressed in timer mode and complex number mode • Many under-the-hood refinements 4.1 01/11/2019 • Send register values to another device running RPN-45: 1. Print registers on paper tape 2. E-mail the tape 3. Copy the mail text and paste into display • Save and restore registers: 1. Print registers on paper tape 2. Long-press any register line on paper tape and drag to the display • Import register values from other sources: 1. Create one value per line, each followed by the desired register number (0..19) 2. Copy desired lines, then paste into display 4.0 09/14/2018 • Extended paper tape sharing (AirDrop, Notes, Dropbox, and more) • Paper tape can be set to bold printing (press the printer's TXT button to see the option) 3.9 08/17/2018 • Now you can backup all registers in a separate area. Great for keeping values handy without risk of deleting them inadvertently, e.g. phone numbers, prices paid for stock shares, etc. – STO Rv = copy registers to backup area – RCL Rv = retrieve registers from backup area – STO (or RCL) x≷y Rv = swap registers with backup area • To clear the stack and all registers, tap the gold key twice and execute CLx. The backup area remains unaffected. • In print mode ALL, all solutions of the linear equation solver are shown on the tape • When computing integral roots of a complex number, e.g. (3+5i)^(1/6), multiple results are returned in X and the registers 1..9 (i.e. up to a total of 10 results) • For statistical calculations, ∑y², ∑xy, ∑x²y are now available in registers R16, R17, R18 • STO x≷y ∑+ swaps statistics registers R5..R8 with extended registers R.5..R.8 • Long-pressing the register view reveals the names of the statistical registers • Improved pasting of values into display, e.g. by dragging from paper tape • Changed input order of weighted mean arguments: x = value, y = weight (frequency) 3.8 04/16/2018 • Fixes a few issues related to the printer About version 3.7: Celebrating the year in which the HP-45 turns 45 with a nice update: • Added logy function (logarithm of x to base y). Even for complex numbers. • Improved trig functions for extremely small angles • Printing stack in complex mode shows imaginary part • All solutions of quadratic or cubic equations are shown on the printer • Printed time values may be copied and pasted into display • Added green ribbon to paper tape printer • Corrections in built-in manual Bug fix: • On restarting RPN-45 in complex mode, the stack was not restored correctly 3.7.1 01/04/2018 Celebrating the year in which the HP-45 turns 45 with a nice update: • Added logy function (logarithm of x to base y). Even for complex numbers. • Improved trig functions for extremely small angles • Printing stack in complex mode shows imaginary part • All solutions of quadratic or cubic equations are shown on the printer • Printed time values may be copied and pasted into display • Added green ribbon to paper tape printer • Corrections in built-in manual Bug fix: • On restarting RPN-45 in complex mode, the stack was not restored correctly 3.7 01/03/2018

RPN-45 HD version 6.5

Updated At: 2026-03-09

Changes: Improved compatibility with real HP-45 when using D.MS conversions: – With „Super-45" set to off: same results as real HP-45 – With "Super-45" set to on: improved results (no digits dropped by conversion) EXAMPLE Convert 12.345612: – "Super-45" off: D.MS-> 12.58225556, then -> D.MS back to 12.34560000 – "Super-45" on: D.MS-> 12.58225556, then -> D.MS back to 12.34561200

RPN-45 HD version 6.4

Updated At: 2025-07-28

Changes: Various cleanups

RPN-45 HD version 6.4

Updated At: 2025-07-28

Changes: Jul 28, 2025 Version 6.4 Various cleanups

RPN-45 HD version 6.3

Updated At: 2025-05-10

Changes: May 10, 2025 Version 6.3 • Faster startup – no delay until the first button press is recognized after switching on.

RPN-45 HD version 6.2.1

Updated At: 2025-03-10

Changes: Mar 10, 2025 Version 6.2.1 • In "Super-45" mode, results such as 9.99×10⁹⁹ now appear correctly rounded both in the display and on the printer for all decimal point settings, e.g. SCI 1 (in contrast to the original HP-45). • Certain calculations, e.g. 100⁷⁵, caused the app to crash. Version 6.2.1 avoids a possible crash when the calculator is not set to "Super-45" mode.

RPN-45 HD version 6.2

Updated At: 2025-03-03

Changes: Mar 3, 2025 Version 6.2 • In "Super-45" mode, results such as 9.99×10⁹⁹ now appear correctly rounded both in the display and on the printer for all decimal point settings, e.g. SCI 1 (in contrast to the original HP-45). • Certain calculations, e.g. 100⁷⁵, caused the app to crash.

RPN-45 HD version 6.1

Updated At: 2024-11-06

Changes: Nov 6, 2024 Version 6.1 • Disabled low-battery indicator (all decimal points lit) when running on Apple Silicon Mac.

RPN-45 HD version 6.0

Updated At: 2024-07-05

Changes: Jul 5, 2024 Version 6.0 • Changed gestures on the "Quick Reference Guide": - Tap to show info screen - Double-tap to show registers - Removed the swipe-up gesture • Thousand separators are now supported in Large Display Digits mode. • In addition to using the Settings, you can toggle Large Display Digits by tapping the gold key, then double-tapping the display. • In addition to "FIX .", thousand separators may be toggled by tapping the gold key, then triple-tapping the display.

RPN-45 HD version 5.7

Updated At: 2023-12-23

Changes: Dec 23, 2023 Version 5.7 • Runs on Apple Silicon Macs (see notes on homepage cuveesoft.ch) • RPN-45 HD requires iOS 12.0 or later