introduction

I don't know how do you drink your tea, but for me it goes like the following:

• Boil water
• Throw in the filter
• taste it
• It's too hot and It burns my tounge
• Let it cool for a while
• Forget about it
• It gets too cold
• Reheat it
• Repeat

And this circle continues until the day has ended, or I get impatient and drink it cold. To end this nightmare I created the Tea Thermometer. It's a little piece of circuit, that plays your favorite tune (which is currently Darude - Sandstorm), when the tea reached the optimal drinking temperature.

Use cases

Although the title says Tea thermometer, It can be used in different situations as well, such as:

• A too hot soup that needs cooling
• A body thermometer which alerts you when you no longer have fever, so you can continue being awesome

The possibilities are endless!

device

The Hardware design is maintained in the TeaThermometerHW repository. To summarize, it has:

• 2 LED 7 segment displays, to display the current temperature
• 2 pushbuttons to interface it
• A CR2032 Coin cell battery, which is supposed to be enough for years of operation! (Well I can't confirm that one yet)
• An STM32l011K4 microcontroller. This is the main device which runs the firmware written in this repository
• A buzzer to produce those sweet tunes

Features

• The optimal temperature is different for everyone, so by long pressing one of the buttons it enters a temperature setting state, where you can set your own optimal temperature.
• The software detects when the device was inserted to the tea, and acts accordingly
• If the device has been turned on, but haven't been put in a hot drink for a while, then it turns itself off to save power.

Future Features

• Battery checking: The device warns the user when the battery needs to be replaced, by checking the battery voltage
• Multiple selectable alert tunes. I'm already getting tired of the current available song..

Build instructions

The project uses the Embedded Template Library as a submodule, so the project should be cloned with the submodules as well:

git clone --recurse-submodules -j8 https://github.com/EdBuilds/TeaThermometer.git
cd TeaThermometer

Prerequisites

To start building the project, currently you will need the latest Eclipse, with system workbench installed, which can be found here

Importing the project

You can import the cloned project to your eclipse workspace, by clicking on the File -> Import projects from file system. Clicking on the Directory... button you can select the cloned repository. Here it should automatically detect an eclipse project, so you can click on Finish

More detailed build instructions are coming later!