Trying to control LED on ESP8266 Pin 7 (via iPhone Hotspot)

Hello all

So, I am trying to create a project with a sketch on the ESP8266 and the Blynk app on my iPhone that simply turns an LED on pin 7 of the NodeMCU ESP8266 board On and OFF.

From the page, I selected I have selected the

Board: NodeMCU
Connection: ESP8266 WiFi
Example: Blynk Blink

I have amended the code to reflect my SSID and password, and I have added the Auth token. So far so good!

Next, building the Blynk project on my iPhone. I created a new project, and added a button, assigned it to digital pin 7.

I have built the circuit with and LED across Pin7 and Gnd.

I have uploaded the sketch.

Now the issue - nothing happens. I see ‘iPhone LED’ (the name I gave my project) is offline.

What am I doing wrong please?


Well, that’s it. Your NodeMCU is not connected. Try to open serial output. What is shows?

Hi Dimitri

I tested the connection using another piece of code, and it connects correctly. I even built a sketch and used some embedded HTML to create buttons for ON and OFF - and that worked fine, both on a web page on my Mac and on the iPhone in Safari.

I will keep trying… maybe it takes a few seconds to connect to my hotspot, so perhaps I should incorporate some loop until it is connected showing the connection status in Serial Monitor.

While you are here - is there a command to return connection status?

I’ll update here if I get it working, thanks so much for replying, much appreciated.


There is a chance your router blocks ports Blynk work with. You may want to check - and detailed - instruction for getting started.

Just managed to get it working, Dimitri! I use an iPhone hotspot for my home WiFi, once I stopped that and restarted it, Blynk connected and it all works.

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