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Integrated Thermometer and Timer

To brew green tea you need water of about 75°C. To know that your water has 100°C is easy, you can see that it is boiling. For 75°C you need a thermometer. Then you also need to take care about the brewing time. It should be usually two minutes.

There are such integrated thermometer and timer things on Amazon, but that's not me cup of tea, I decided to build one on my own. It should run on batteries, it should be small and it should make no noise (for office use).

In between I was reading "Patterns for Time-Triggered Embedded Systems" from Michael Pont. And afterwards I was curious to use such a simple cooperative scheduler instead of the super-loop, as it is common in the Arduino domain.

I used a MSP430G2553 with 10bit-ADCs, a PT1000 sensor and two seven-segment LED displays.

The code is available at https://bitbucket.org/wollud1969/teathermotimer https://gitlab.com/wolutator/TeaThermoTimer.

Schematics:
201609091558_0001

Calculation for measurement:
201609091558_0002