WARNING: requires 1.5k of RAM, so be careful about which microcontroller you put it on! Technically, it should work on a MEGA 2560, but I haven't tried it yet.

edit: it does work on a MEGA but the raw code doesn't compile for the UNO because of flash related problems. Please remove all branding icons (a_png*) except a_png0 and a_png1, and the draw code related to it.

Source and pictures can be found here and, hopefully, only here.

It uses Bodmer/TFT_ST7735 (and possibly adafruit/Adafruit-GFX-Library) libraries. It also uses EEPROM.h and SPI.h.

• Arduino IDE

• iProgramInCpp

See also the list of contributors who participated in this project.

This project is licensed under the MIT License, which should be provided here.

These instructions will help you make yourself a device able to run NanoShell (assuming you've got the right components) for development and testing purposes.

Make sure that the buttons are normally open and are momentary switches.

• UP -> Arduino pin 2,
• DOWN -> Arduino pin 3,
• LEFT -> Arduino pin 4,
• RIGHT -> Arduino pin 5,
• A Button -> Arduino pin 6,
• B Button -> Arduino pin 12.

• RST -> Arduino pin 7,
• CS -> Arduino pin 9,
• D/C -> Arduino pin 8,
• DIN -> Arduino pin 11,
• CLK -> Arduino pin 13,

WARNING: Please change to these pins in the TFT library's "User_Setup.h" file or the screen will not work properly!

NanoShell allows you to utilize the leftover space from flash and RAM (or even optimize it) to make your own apps. Here are a few steps:

1. Create your own icon and make it into a 2bpp image (B00 is transparent, B11 is black, B10 is white and B01 is the palette defined color) (this is done to save on RAM) and put it in ICONS.h
2. Add your own app on the main menu by going to SCREEN.h and finding DrawDesktopI(). Here you can find all the routines to draw the main menu. Simply copy an app icon draw statement and add 18 pixels or so to the Y value.
3. To make your app runnable, goto AVRDEFF.h/loop() and find the switch(SelectedApp) case. Add your own app there and write a Start function. Make sure to redraw the desktop once the Start function returns. After that, go to SCREEN.h and add 1 to APP_COUNT. You'll need this to be able to select and run your app.
4. Create a new header file (e.g. MyCoolApp.h) and add it into the app includes in NANOSHELL.ino right before AVRDEFF.h
5. Create a main function and run it from your Start function.
6. Start coding away!

Good app design should include:

• A main loop for user input
• Reused kernel functionality (to save on RAM)
• Use the F() macro when possible (for example in tft.print())

Once the kernel has started running your app, you can't go back without returning from your main function. (This is similar to regular apps but not exactly) On Windows you can request an exit out of an app at any time. Here you can't. So please give the user a chance to exit without resetting if possible, please :)