You are going to learn how you can control a relay that is attached to your Raspberry Pi, from any device like your computer or tablet. To add scripts to OctoPrint and turn on and off LED lights, of course this LED could be replaced by anything like a lamp, or the motor of your electric curtains.
I bought two high accuracy RTC (real time clock) modules. They can run for years off of a coin cell battery, even when the Arduino loses power, or is reprogrammed. Both of these modules are special in they claim higher accuracy than your typical RTC. What is a RTC?
I will show you how to connect and program a 0.96" i2c OLED display module to an Arduino Nano, in this tutorial a 0.96 inch monochrome OLED display is connected to an Arduino Nano. Libraries are then installed and some example programs run which show how to use the display in an Arduino sketch.
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