The Scientific Raspbian Calcuberry Pi
This project is an attempt at making an affordable, DIY scientific calculator that offers better performance and results in more productivity than the (IMO) overpriced TI calculators that many students are forced to use.
The main components of this repository are listed below:
- Raspberry Pi model B
- 2.8” 320x240 touchscreen display
- 10,000 mAh battery
- Keyboard PCB
- Kailh Burnt Orange box switches
- PBT key caps
- Teensy 2.0 microcontroller
- 3 150 Ohm resistors
- 2 5000 Ohm resistors
- screws/threaded cylinders
- 2 small USB -> micro cables
- 1 nice toggle switch
This project has not been completed yet, and parts of it are still being designed, but the assembly will mainly consist of screws, threaded cylinders, and a somewhat complex 3d printed case with a sliding panel for “maintenance”.
The keyboard for this project is based on Will Yager’s custom mechanical keyboard project (blog post) for a full split keyboard with two halves. We will only use one half per calculator, which is close to the ideal size for a scientific calculator.
Incomplete, but will be made for a Teensy 2.0, the same as the original project by Will Yager.
As stated, the project is not complete, so these plans may change. A regular scientific calculator has 50 keys, however this one will have 33, so we will need to make a few compromises. The “2nd”, “Alpha”, and “Power” keys will be mapped to the three backlit keys on the keyboard and will light up when active, however the “power” button will actually put the device to sleep (and light up when in sleep mode - there will be a physical switch to turn it completely off and on). To save room, the letter keys will still be accessible in alpha mode, but will consist of a T9 layout on the number keys, not across the entire board like is common for most TI-86 calculators.
As of now, I am not sure what software I plan on using, but I will attempt to make the keyboard settings work universally - and not for any specific piece of software - as much as possible (for example, the sin/cos/tan buttons will print out the characters “sin(“, but not the end parentheses, as some software will insert them automatically.