Wi-Fi Credentials to Your ESP8266 via Pulsing Mobile Screen

Eduardo Zola has solved the age old problem: How do you set the Wi-Fi access point and password on your Wi-Fi device without the Wi-Fi connection working? Adding a keyboard and screen is expensive and unnecessary. What to so?

His solution is simple and very inexpensive, genius really. Use an inexpensive light dependent resistor (LDR) and a mobile phone. You enter the Wi-Fi credentials in the phone and place the ESP8266 with the LDR over the phone. A series of coded flashing from the phone sends the credentials to the LDR and let the ESP8266 know the information via a simple light encoding.

ESP8266 + LDR

You can see the circuit and code on his GitHub page.

Have a clever way to configure Wi-Fi on your Internet of Things project? Let us know in the comments!


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1 Comment

  1. This is how the Electric Imp system works (called BlinkUp), and I believe they patented it.

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