48sx, a vintage RPN calculator

czodroid

About this app

48sx: The HP48 SX Emulator!

The HP48 SX is a vintage RPN calculator that many of us remember with fondness. I used this calculator 30 years ago and fell in love with it. Now, I can carry it in my pocket every day!

The HP48 SX emulator for Android is available on the Play Store and GitHub. The bundled ROM is free for non-commercial use. No nags, no ads, and completely FREE!

- Play Store: https://play.google.com/store/apps/details?id=org.czo.droid48sx
- Releases apk: https://github.com/czodroid/droid48sx/releases
- Sources code: https://github.com/czodroid/droid48sx

48sx is a modified version of droid48, specifically tailored for the HP48 SX. Credit goes to Arnaud Brochard (author of droid48 for Android) and Eddie C. Dost (author of x48 for UNIX), who created an emulator of the Saturn processor in 1990.

48sx CHANGELOG
===============

* 15 Aug 2024 (Version 14.1.28728418)
- Bug fixes and performance improvements
- Intended to work from Android 5 to 14 on armeabi-v7a, arm64-v8a, x86 and x86_64 architectures
- In recent versions of Android, you must grant the 'Photos and Videos' permission for 'Load object on stack' and 'Save/Restore checkpoint ZIP' to function properly. The file must be located in the Download folder and have a '.png' extension.

* 11 Feb 2024 (Version 13.1.28459983)
- Bug fixes and performance improvements
- Intended to work from Android 4.4 to 13 on armeabi-v7a, arm64-v8a, x86 and x86_64 architectures
- On Android 13 (API 33), you must grant the 'Photos and Videos' permission for 'Load object on stack' and 'Save/Restore checkpoint ZIP' to function properly. The file must be located in the Download folder and have a '.png' extension.

* 26 Aug 2023 (Version 2.42.28217746)
- Bug fixes and performance improvements
- Intended to work from Android 4.4 to 13 on armeabi-v7a, arm64-v8a, x86 and x86_64 architectures
- New name for checkpoint ZIP: Download/48sx_cp_$DATE.zip
- New SVG icon for Android above Oreo (Android 8, API >= 26)

* 10 Jul 2022 (Version 2.42.27624074)
- Bug fixes and performance improvements
- Intended to work from Android 4.4 to 12 on armeabi-v7a, arm64-v8a, x86 and x86_64 architectures
- Fixed the "Large LCD" option in the settings, and replaced it with "HP48 LCD" to get full pixels
- The HP48's LCD screen has now a maximum width on your device, but you can set "HP48 LCD" in the settings get full pixels

* 4 June 2022 (Version 2.42.27573940)
- Bug fixes and performance improvements
- Intended to work from Android 4.4 to 12 on armeabi-v7a, arm64-v8a, x86 and x86_64 architectures
- Haptic feedback enabled by default, but can be disabled on settings
- New menu: 'Save checkpoint ZIP As...' : save the current checkpoint in a zipped file (in Download/checkpoint_$DATE.zip). This zip file must contain the files ('hp48', 'rom', 'ram' and maybe 'port1' or 'port2')
- New menu: 'Restore checkpoint ZIP' : restore from a zipped checkpoint.zip (that you choose)
- Permissions on "Choose File" works on some Android 11 and 12, depending on the brand. This will be my next update...
- When the action bar is enabled, pressing an hp48 button disables it again
- Checkpoint is saved at the first startup and new functions to load a stuck HP48
- New shortcuts, one for full reset, and another to restore from a checkpoint when the emulator is stuck

Ratings and reviews

Most excellent trip in the way back machine! I recently discovered that HP48g was dead just as I'm doing a homework set for my first week back at grad school. I don't really want a new calculator and I really don't like using excel for simple math. As others have mentioned this is like sitting down to the bar with an old friend. Lots of muscle memory still works and other than the loss of a clicky button and a slightly squished aspect ratio it seems to be my old trusty calculator.

I like everything about this calculator, except for one idiosyncracy, and that one issue is why I rarely use the app: you have to hold the buttons too long for a key press to register. The haptic vibration comes quickly enough, but you have to remain on the button for significantly longer. It is too long for me.

In past few months, app continually crashes, with deleting / reinstalling the only way to clear the problem. Today I tried to do. 56 x 280 and it crashed. This time I won't be reinstalling. MAY 2019. I have galaxy s9+. Update: the latest update 19oct19, appears to have fixed my crashing issue. This is the best RNP calculator app (even when it was crashing, I keep deleting and reinstalling as I couldn't find a better app).

What’s new

- Intended to work from Android 5 to 15 on armeabi-v7a, arm64-v8a, x86 and x86_64 architectures
- In recent versions of Android, you must grant the 'Photos and Videos' permission for 'Load object on stack' and 'Save/Restore checkpoint ZIP' to function properly. The file must be located in the Download folder and have a '.png' extension. I hope it will be OK for Google Play!