Distance with HC-SR04

[onlize]

I configured ESPEasy with HC-SR04 sensor.

I configured it using this https://www.letscontrolit.com/wiki/index.php/HC-SR04. I used the option with two resistors. The only difference is that I have NodeMCU and it does not have pin with 5V, and I had to connect VCC pin on HC-SR04 to 3.3V pin on NodeMCU.

The problem that I have is that the output is always 0.10 and does not change. Is it possible that the problem is 3.3V instead of the 5V? Do I have to buy 5V power supply for the HC-SR04 sensor? Or is there anything else that I should check?

Thank you.

[TD-er]

The wiki page you linked does state something about the voltage:

The HC-SR04 must be run on 5V. Running it with 3,3V will show very weak results or nothing at all.

But the NodeMCU does have 5V, when powered via USB?
Or are there newer/other versions I don't know yet?
Also take into account you really need something to lower the 5V signal from the sensor.

[onlize]

As far as I can see, it does not have 5v pin:



I guess, I have try to get 5V power supply.

Thank you.

[grovkillen]

Vin is 5V

[onlize]

It worked, thank you for your help.