The code (Arduino sketch) is a basic one without any dedicated SIM800L ... int relay = 13; // Output for Relay Control void setup() { pinMode(relay, OUTPUT); digitalWrite(relay, LOW); // Initial state ...

What was your first Arduino program? Probably an LED blinker — that seems to be the “hello world” of microcontrolllers. You probably moved on to things a little more complicated pretty quickly.

I just received my RC522 RFID reader and made this simple Arduino access control system that uses the reader, a buzzer for the alarm and a relay shield for the security ... but I will talk about the ...

First things first, there needs to be a way to turn the current control knob on the AC ... can also be set without uploading a new sketch to the Arduino. From the temp vs time graph, it looks ...