Hardware Overview
The Qwiic LED Stick is a fairly straightforward ATTiny85-based Qwiic board that you may be familiar with already.
In this section we'll cover the hardware present on the board in detail.
ATTiny85
The brains of the Qwiic LED Stick is one of our favorite microcontrollers, the ATTiny85. This IC comes pre-
programmed with custom firmware designed to interact with the Arduino library and Python package we've written
to use with this board. The ATTiny85 accepts I C reads and writes, interprets them and outputs the appropriate
strings to control any APA102 LEDs attached to it.
The default I C address of the ATTiny85 is
0x23
. Adjust the address either through the ADR jumper or via
software. Read on for more information regarding changing the address in both manners.
Just like our other Qwiic breakouts using the ATTiny85, users can update or change the firmware using the 2x3 pin
header on the back of the board. The firmware can be found in the Hardware GitHub Repository. For tips and
tricks on how to re-program an ATTiny IC, check out this tutorial.
APA102C LEDs
The LED Stick includes 10 APA102C LEDs controlled by the aforementioned ATTiny85. APA102C LEDs operate
just like most addressable LEDs over a two-wire interface. The board ties that interface to the ATTiny85 and
operates both the IC and LEDs at
3.3V
logic. For specific information regarding the LEDs, take a look at the
A tutorial to help figure out the power requirements of
your project.
Learn the difference between 3.3V and 5V devices and
logic levels.
An introduction to I2C, one of the main embedded
communications protocols in use today.
This tutorial will show you how to communicate with
your serial devices using a variety of terminal emulator
applications.
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