This is a quickstart explanation of what Adafruit Arcada library provides, see the detailed Doxygen documents for arguments & return values


  • arcadaBegin() must be called first, it will set pin directions, turn off NeoPixels, and check for connected hardware
  • filesysBeginMSD() will initialize the storage method (SD or SPI flash) and check if a proper filesystem exists. On SD cards that's a FAT filesystem (so make sure its formatted). On SPI Flash we use CircuitPython's FAT filesystem, the best way to format is to load CircuitPython on once. If you're using TinyUSB as your USB stack, this will also make the disk drive appear on a computer
  • displayBegin() initializes the display, you will need to turn on the backlight after this is done - we don't do it for you!

Joystick & Buttons

  • readJoystickX and readJoystickY read the analog joystick (if there is one) and returns -512 to 511 with 0 being 'center' (approximately)
  • readButtons returns a 32 bit mask for each button pressed at the moment of the function call - right now only the bottom 8 bits are used. Check Adafruit_Arcada_Def.h for the button mask names. Analog joysticks are checked against a threshold and 'emulate' a button press

Some boards, like the MONSTER M4SK and HalloWings, do not have a proper joystick - instead we will return the capacitive touch pads or buttons as if there was a joystick. For example, the M4SK's three buttons will return 'up', 'A' and 'down' respectively.

  • After readButtons is called, justPressedButtons will tell you buttons were pressed as of the readButtons call
  • Ditto for justReleasedButtons

Backlight, Speaker and Sensors

  • Enable/disable speaker amplifier (if there is one) with enableSpeaker - this doesn't affect headphones if there are any
  • readBatterySensor returns the battery voltage detected. You cannot detect whether a battery is being charged, only the voltage.
  • readLightSensor will return 0 for dark, 1023 for bright surrounding light.
  • setBacklight can set the backlight from 0 (off) to 255 (all the way on)

Alert Boxes

These info boxes and alert display on the screen to let the user know something they need to do, get ready for, or went wrong. You can have the alert wait for a button press or have it return immediately (then you can delay or wait for something else to occur)

  • alertBox is the generic, you can set the message, box and text color, as well as button press
  • infoBox is an alertBox where the default button is A and the box color is white, text color is black
  • warnBox is an alertBox where the default button is A and the box color is yellow, text color is black
  • errorBox is an alertBox where the default button is A and the box color is red, text color is white
  • haltBox is an alertBox where the box color is red, text color is white. It will sit in a busy loop and never return

This guide was first published on Aug 15, 2018. It was last updated on Jul 21, 2024.

This page (Arcada Library) was last updated on Mar 08, 2024.

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