Adafruit QT Py Activity Timer User Manual
Adafruit QT Py Activity Timer and Hydration Reminder
Created by Kattni Rembor
Last updated on 2021-02-15 10:26:23 AM EST
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Guide Contents
Guide Contents
Overview
Parts
Assembly
Assembly
Optional Diffusers
CircuitPython
Set up CircuitPython Quick Start!
CircuitPython Libraries
CircuitPython Library Bundle
Library Install Troubleshooting
Activity Timer
Code
Settings and Customizations
Using the Activity Timer
Hydration Reminder
Code
Settings and Customizations
Use the Hydration Reminder
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Overview
It's easy to get focused on a task, and forget to take a break, or even eat lunch. Perhaps you find that you
aren't drinking enough water throughout the day. Sometimes you simply need some assistance
remembering things! This project is here to help.
This guide will show you how to build a customisable LED timer using the Adafruit QT Py, the LIS3DH
accelerometer, and two NeoPixel LED rings. It's meant to be compact and sit on your desk. The rings light
up to let you know the timer is running. Set it on its side to turn off the timers and the LEDs.
For the activity timer, you'll set a duration for two different activities, such as 120 minutes of work and a 15
minute break. Plug it in, start the timer and it will gently fade between two colors to let you know time is
passing. When it reaches the end it stays at that color for a bit before blinking at you to remind you that
you haven't moved to the next task. Flip it over to begin the second timer, and the process repeats.
For the hydration reminder, you set the interval you'd like to be reminded to drink water, such as once
every 60 minutes. Plug it in, start the timer, and the process is the same as the activity timer. In this case,
when you flip it over, it counts down the same amount of time.
Parts
This build uses the 50mm long STEMMA QT cable listed below. The 100mm long STEMMA QT cable
(https://adafru.it/FNS)would also work, but would require taming the extra cable length.
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Adafruit QT Py - SAMD21 Dev Board with STEMMA QT
What a cutie pie! Or is it... a QT Py? This diminutive dev board comes with our favorite lil chip, the SAMD21
(as made famous in our GEMMA M0 and Trinket M0 boards).For...
$6.00
In Stock
Add to Cart
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NeoPixel Ring - 16 x 5050 RGB LED with Integrated Drivers
Round and round and round they go! 16 ultra bright smart LED NeoPixels are arranged in a circle with
1.75" (44.5mm) outer diameter. The rings are 'chainable' - connect the...
Out of Stock
Out of
Stock
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Adafruit LIS3DH Triple-Axis Accelerometer (+-2g/4g/8g/16g)
The LIS3DH is a very popular low power triple-axis accelerometer. It's low-cost, but has just about every
'extra' you'd want in...
$4.95
In Stock
STEMMA QT / Qwiic JST SH 4-Pin Cable
This 4-wire cable is 50mm / 1.9" long and fitted with JST SH female 4-pin connectors on both ends.
Compared with the chunkier JST PH these are 1mm pitch instead of 2mm, but...
$0.95
In Stock
Add to Cart
Add to Cart
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Hook-up Wire Spool Set - 22AWG Solid Core - 6 x 25 ft
Perfect for bread-boarding, free wiring, etc. This box contains 6 spools of solid-core wire. The wire is easy
to solder to and when bent it keeps its shape pretty well. We like to have...
Out of Stock
Out of
Stock
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USB Type A to Type C Cable - approx 1 meter / 3 ft long
As technology changes and adapts, so does Adafruit. This USB Type A to Type C cable will help you with
the transition to USB C, even if you're still...
$4.95
In Stock
Add to Cart
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Assembly
The following shows how the parts are wired together. Assembly of the timer involves some creative use
of wire length to suspend the QT Py and LIS3DH between the two rings.
Data In on ring one to A3 on QT Py
V+ on ring one to 5V on QT Py
Gnd on ring one to GND on QT Py
Gnd on ring two to GND on ring one
V+ on ring two to V+ on ring one
Data In on ring one to Data Out on ring
two
LIS3DH to QT Py using STEMMA QT cable
Assembly
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Begin by soldering the three wires to each ring, using piece
of wire 5-6 inches in length.
Solder the blue wire to In (data input), the black wire to G
(power signal ground), and the red wire to V+ (power 5V DC)
on both rings. Solder the data input wire first, and follow the
pattern indicated in the second image where green indicates
the through-hole to use to solder the wire, and red indicates
a through-hole to skip.
Trim any excess wire sticking up above the LEDs.
Choose a ring to be ring one.
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Bend the wires on ring one to match the locations of the pins
on the QT Py, with enough wire to suspend the QT Py above
the ring.
The blue wire should match A3, the red wire should match
5V and the black wire should match GND.
Make sure the QT Py is parallel to the ring - if you lay the ring
flat on your desk, the QT Py should also be horizontal.
Solder the wires to the QT Py.
© Adafruit Industries https://learn.adafruit.com/qt-py-activity-timer-and-hydration-reminder Page 10 of 32
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