Peanut GB
Peanut GB is a Gameboy emulator. Do you want to play your original Game Boy cartridge on your NumWorks calculator? This is the app for you!
How to get games
We can't provide you any games, because of legal reasons. However, you can download games from the internet easily. A search like "gameboy roms" should give you plenty of results.
You will need to add your rom as an external file. To do so, follow the instructions in the how to install guide.
How to play
It’s quite obvious, given how the NumWorks’ keypad looks just like a Game Boy’s. Anyway, here’s a list of the bindings between the NumWorks’ keypad and the Game Boy’s:
| Game Boy | NumWorks |
|---|---|
| Arrow keys | Arrow keys |
| A | Back |
| B | OK |
| Select | Shift |
| Select (Alternate, see below) | Home |
| Start | Backspace |
| Start (Alternate) | Alpha |
| Start (Alternate, see below) | On/Off |
| Toolbox | Write current save to storage |
| 0 | Write current save to storage and exit |
To modify the behavior of the emulator, you can use theses keys:
| Key | Action |
|---|---|
| 1 | Use the original game boy palette |
| 2 | Use a pure greyscale palette |
| 3 | Use an inverted greyscale palette |
| 3 | Use Peanut-GB original palette |
| + | Render the screen in fullscreen |
| - | Render the screen with the original aspect ratio |
| 7 | Show frame timings |
| 9 | Enable On/Off and Home keys, and suspend the calculator |
Download
You can download the Peanut-GB app from this link:
Warning
Peanut-GB (Color) require more RAM and use more CPU time, so some games won't work at all or will not work in realtime (e.g. 2 second in the real world will last 1 second in the game). Most Gameboy Color games can run on normal Peanut-GB in greyscale for better performance.
Tips
At the time, only Peanut-GB v1.1.0 and later support games saves, so you won't be able to save you game on Peanut-GB (Color) for now.
Installation
To install the Peanut-GB app, follow the instructions in the how to install guide.
About On/Off and Home keys
External apps can't use On/Off and Home keys for control as the kernel detect if these keys are pressed and react by exiting the app (and suspending the calculator for the On/Off key).
As an user, the only thing you probably want to know is that you need to press the "9" key on the keyboard enable the On/Off and Home keys. It will suspend the calculator, so you just need to press On/Off after that to restore your game. You need to do this every time you enter the emulator.
It also have the nice side effect of allowing suspending the calculator without exiting the emulator which is useful in a lot of situations. For example, is you need to temporary suspend the calculator in a hurry as the teacher is coming, all you need to do is pressing the "9" key (but you are not playing during class, right? -insert Anakin and Padme meme here-)
For the technical details on what exactly happen when you press the 9 key, see below:
There is no API to disable explicitly this unwanted behavior. To work around this issue, we call the kernel method for enabling USB which, among other things, disable the interrupts and handling of On/Off and Home keys. It also shut down the keyboard (except the back key), so we need to power it back on. Hopefully, when the calculator goes out of sleep, keyboard is reinitialized, but not interrupts.
This is a bit hacky, but at least it's working and better than nothing. An official implementation from NumWorks would be useful, but who know if they are planning to implement API for external apps… There is no official API for using the storage, external apps are using an implementation directly reading the RAM the same way as computer does to read and write files in the calculator, so we are far away from getting a method to disable On/Off and Home.
A more complete explanation is available in the documentation.
Source code
Source code for Peanut-GB v1.1.0 and later is available here.
Source code for Peanut-GB v1.0.0 is available here.
Source code for Peanut-GB (Color) is available here.