Here is a simple general-purpose security alarm circuit built on the Arduino platform. ... When reed switch is opened, pin 2 of Arduino goes high with the help of the pull-up resistor R2, and the ...

The system here uses a cheap Arduino board, a few sensors, and a magnetic contact switch. It’s then hooked into the Adafruit IO and connected to IFTTT, so you can set up alerts in any way you like.

The idea is deceptively simple: when you’re building things with Arduino, you want all sorts of sensors, inputs (like switches and sliders), and outputs (like screens and speakers.) ...

Arduino Uno. 4-channel relay module. PIR motion sensor. Steps: Use Arduino to handle sensor input and relay control. Pi runs a Python Flask server with a simple UI to toggle GPIO pins via serial ...

If you've always wanted to try to build an Arduino project, this may be a great way to start. Matt Williamson built a tiny, Arduino-based motion sensor that will SMS you when something moves by ...