Learn how to control temperature and humidity with Arduino Nano using DHT22 sensor and 1602 I2C LCD display.
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In this article, we will consider how to create a laser alarm that will notify you when someone passes by it. It will be an excellent project for beginners in the field of electronics and programming. Laser alarm can be useful for the security of the premises or just as an interesting automation experiment.
A breadboard and a set of wires
Active buzzer (the author condemns slavery)
Computer/laptop
Anode (marked on the case, positive pin) → D3 pin of the ESP8266
Cathode → GND ESP8266
Cathode (shorter lead) → GND ESP8266
Anode → to a 100 Ohm resistor. Resistor to pin D4 ESP8266
D0 → пін D5 ESP8266
GND → GND ESP8266
VCC → пін 3V3 ESP8266
S → D6 pin of ESP8266
– → GND ESP8266 ESP8266
Central contact → pin 3V3
The laser must be placed directly in front of the light sensor so that the beam hits the photodiode. ESP8266 can be powered via a regular USB.
**If you do not have the Arduino IDE installed, I advise you to watch the video tutorial, which shows how to install and configure it.
At this link you will find information on how to download the firmware to the ESP8266.**
Download the firmware from this link and download it to the ESP8266 according to the instructions above. Also, for work, you need to create a bot in Telegram and find out your id.
Importantly! You need to flash the ESP8266 before connecting all the components. If batteries or other parts are connected to it during the firmware, you risk burning (literally) your computer and ESP8266.
It is quite simple: if the laser does not shine on the photodiode, the ESP8266 understands that someone (or something) is in its way, and warns about it. We hope that everything worked out for you!
If you have any problems, you can contact us at [email protected].
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