JRPN 15C/16C - User Guide

This is the user guide for JRPN 15C and JRPN 16C calculator simulators. The main page is here.

Both simulators try to be a faithful implementation of the behavior of the original 1980s calculator. For the most part, the user guide for the original calculators applies. It can readily be found on the internet. Those guides aren't copied here because I'm unsure of copyright, and JRPN is a clean-room implementation.

This guide concentrates on some slight extensions, and various settings that are part of the application. Be aware that the calculation results in floating point modes can be expected to diverge somewhat from the original calculator. JRPN maintains floating-point numbers internally as a binary-coded decimal value with a ten digit mantissa, like the original. However, for many calculations, the value is converted into a standard 64 bit double, then the calculation is performed and the result is converted back. Other operations, like the 15C's integrate and solve functions, almost certainly use a different algorithm than the original. With this said, results are believed to be generally compatible, and in some cases slightly more accurate.

The ON Button

The original calculators let you access special functions by simultaneously pressing the ON butten and some other buttons. In the simulator, press the ON button once to access these functions; pressing it a second time quits the program. The other "hidden" features are swapping commas and decimal points ("Euro mode"), a calculator reset, and a calculator self-test.

Settings

Note that some settings are only available on mobile platforms (Andriod and IOS).

• Show Menu Icon - If unchecked, gets rid of the Android-style dots that provide a visual cue that a menu is there. In this mode, you still access the menu by pressing in the upper-right hand corner of the UI.
• Disable System UI Overlays (mobile) - Hides Android/IOS system UI elements, so you just see the calculator.
• Orientation (mobile) - Lets you lock the orientation to portrait or landscape. Personally, I leave this locked to landscape, since this simulates the real calculator.
• Key Feedback - Lets you force a key feedback different than the platform default. For example, on Android the default platform key feedback is a click, but I prefer haptic feedback. If you want key feedback on Android, make sure you have "Touch sounds" and/or "Touch vibration" enabled in your device settings. See also Issue 63. "Heavy" haptic feedback might be any different, depending on your phone model.
• Long Numbers - Controls how long numbers are displayed, like "123456789ABCDEF0 h" or "-1.234567891 27". The default is to behave like the original calculator. In landscape mode, the LCD display can be stretched enough to fit a 64 bit hex number. The digit size can also be shrunk to fit more in.
• Show Accelerators - Shows keyboard accelerators.
• System Settings, ms/Program Instruction - lets you control how fast programs execute. By default, the calculator delays for 50ms after each instruction, which generally yields performance about 3x the original in my experience.
• System Settings, Colors - lets you tweak various colors in the UI, by entering a hex RGB value. For example, if you like a slightly different shade of gold for the F key, you can set it here.
• System Settings, Debug Log - captures debug information, including a record of keypresses, in an internal memory buffer. This information is included if you copy the calculator state to the clipboard in the File menu, and might be useful for a bug report. To date, this has never been necessary.

File Menu - Read

• Restore Starting State - Restores the calculator to its last saved state.
• Read from Clipboard - Reads calculator state from the clipboard. This can be used to copy it from JRPN on another device, by sending the string and copying it to the clipboard.

File Menu - Save

• Save as Starting State - saves the current calculator state. The calculator does this automatically when it's shut down or when you turn it off using the ON button, so normally this isn't needed.
• Copy to Clipboard - Copies the current calculator state to the clipboard. You can use this to send it to another copy of JRPN on a different device.
• Export to Application - Like Copy to Clipboard, but sends the data to another program, e.g. using an Android intent.
• Copy URL to Clipboard - Like the previous two, but encodes the state as a URL that can be used to launch the web version of JRPN.

File Menu - Import/Export Program

These menu options let you import and export a human-readable program listing. It may be possible to use this to send and receive programs to/from other HP 15C/16C simulators. The format is based on the documentation from Torsten's HP 15C Simulator. I added this feature at Torsten's request.

Reset All

Restores the simulator to its default settings.

Bill Foote