Back in November, Rayshobby Shop officially launched SquareWear 2.0, an open-source, wearable board powered by Atmel’s ATmega328 MCU.
The board – which runs at at 3.3V and 12MHz – is equipped with large pin holes to allow conductive thread to be stitched through. Makers can also solder wires directly, or solder snaps for quick attachment and detachment from textiles.
This week, Rayshobby Shop rolled out a smaller version of SquareWear, along with a chainable color LED matrix and an interactive design tool. Similar to SquareWear 2.0, the SquareWear Mini is built around Atmel’s versatile ATmega328 microcontroller.
Key specs include a USB port, power switch, pushbutton, buzzer, temperature sensor, light sensor, MOSFETs, lithium battery jack and lithium battery charger. Plus, the pins boast enlarged sizes for sewing with conductive threads, soldering sew-on snaps and touch sensing.
“How did I shrink it to be smaller than the original SquareWear? Well, by removing the on-board rechargeable coin battery and color LED, [while] routing some pins to the side,” Ray explained in a recent blog post.
“With the space saved, I was even able to add a 16KB I2C EEPROM for storing extra data. These changes were made because SquareWear designed specially to be attached to a chainable color LED matrix. This will enable a whole new set of exciting projects, as you can see [in] the video above.”
In terms of the LED matrix, each contains 35 WS2812B color LEDs arranged on a 5×7 grid with 8mm spacing.
“These are great because the LED has a built-in chip that allows you to daisy chain them in bulk and still be able to individually set the color of any LED with only one MCU pin,” Ray continued.
“Adafruit calls them Neopixels. No matter how many LEDs you have, you only need 3 pins to get them to work, namely the VCC, GND and DATA_IN pins.”
More specifically, the pins are strategically mapped out at the back of the LED matrix, with the locations matching up to the VCC, GND and digital D10 pins on SquareWear Mini. Meaning, Makers can easily link the SquareWear Mini with the LED matrix by either soldering some sew-on snaps or directly soldering the two boards together.
On the software side, Ray said he re-worked the SquareWear software library to include LED matrix demos, which run on both the original SquareWear 2.0 and SquareWear Mini. The demos – included in the pre-configured software package – are also available for download individually at the SquareWear Github repository.
Interested in learning more? You can check out Ray’s original SquareWear Mini blog post here.
Atmel | Bits & Pieces 