[Dustin Andrews] built this add-on board which works as a proximity sensor. He wanted a standalone sensor for his Arduino projects which would use a single pin as a trigger. This lets him alert the… ...

It should be a piece of cake if you program your Attiny85 chip (not Digispark) using your existing Arduino IDE with the help of one “USB tiny ISP (v2.0)” programmer. The software/Arduino sketch /* * ...

Here is a tested Arduino project that uses 3 sensor probes as water level indicator with 3 leds and one LCD display + a simple controller that turns on a motor when the water has reached the desired ...