Nodemcu not booting with ds18b20 if connected to 3v but does with 5v (but then it doesn't work)

ESPHome
1

Hi! I have a very simple setup but it is driving me crazy.

I have nodemcuv2, and ds18b20 with YL-10. My ESPhome config is simply:

dallas:
  - pin: D8

sensor:
  - platform: dallas
    address: 0x970315a4c4b8ff28
    name: "Sauna Temperature"

Now, when:

  1. I connect the YL-10 (which then goes to ds18b20) to any of the 3v outputs on the board, the nodemcu does not start after a reboot/loss of power (that is an issue for my set up). It boots up fine when I disconnect the YL-10 from 3v and reset the board, and THEN I connect it to 3v. The measurements go in just fine.
  2. when I connect it to VIN, it boots up fine, but the light on YL-10 do not turn on and the measurement does not work at all (empty reading).

I cannot find anything on the internet what might be causing this. I tried different power supplies. Any help, please?

2

Im not sure why you chose to use D8 but doing a simple pinout reference on your board BEFORE you start wirng things to it, it will save you on an enormous number of errors and Oopses. D8 is one of those pins that can be used under certain circumstances but, its generally a pin thats best not used. In this case the documentation clearly tells you the data gpio needs pulled high with a 4.7k resistor and if you look at your pinout it yells you D8
is pulled LOW and it wont boot up if you pull it high. If you get in the habnit of checking this, you wont have these problems. Where did you get the 1-wire address to use for this sensor if you cant get it working and your unable to retrieve the address from the logs which is more or less the standard process for setting these up?

Screenshot_20231222-050849_Samsung Internet
Screenshot_20231222-050849_Samsung Internet1080×2280 193 KB

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3

Thanks for helping, I don’t have a good excuse, just messed up and didn’t notice.

Where did you get the 1-wire address to use for this sensor if you cant get it working and your unable to retrieve the address from the logs which is more or less the standard process for setting these up?

I was able to get it booted up, then connecting, then getting the address. :person_shrugging:

4

It happens. Theres so much stuff you have to understand and learn when you get into this hobby. Just keep in mind just about every pin on any board will have more than one use. Sometimes its main putpose is a standard gpio but other times its something important. Keep those pinout charts handy for all the boaed types you use. It will help you greatly.

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