ESP32 and not findi...
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ESP32 and not finding 1Wire  


Trusted Member
Joined: 2 years ago
Posts: 52
June 17, 2020 12:13 am  


So I have the simplest of configs so far

EDP32 dev board and a single 1Wire DS18B20 probe wired in.

Power to breadboard
Ground to GND pin
Data to breadboard

I then have 4.7K resistor plugged in after Power and Data in breadboard
Power goes to 3.3V pin
Data goes to GPIO 5

I get no readings in Coms area of interface

If I compile simple DS18B20 project to ESP32 picks up 1Wire probe and reads temps straight away.

I tried flashing with 45E and 45H firmware, but exact same result.

Sometimes it will pick up the 1Wire and transmit temps, but it will flake out again pretty quickly.

I've tried 3 diff ESP32 dev boards, and 3 diff temp probes. All work under the simple ESP32 DS18B20 project.


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Trusted Member
Joined: 2 years ago
Posts: 52
June 17, 2020 3:10 am  

Just thought I'd add I'm on BruControl version 1.1 build 0 in case there has been any releases since way back when

Reputable Member Admin
Joined: 4 years ago
Posts: 279
June 17, 2020 5:28 am  

Depending on the sketch you are using, if it works there it should in BruControl. 1-wire works reliably on ESP32 in our experience.

Please remember you cannot hot-swap. The sensors are enumerated on interface boot-up, so adding or removing sensors will require a bus reset, which you can issue via '%3' into the communications dialog. Make sure you are reading sensor index 0.

How long is the wire? Are you sure the resistor is correct? Is the wiring firm and away from any noise generating devices? How is the ESP32 powered? What do you mean by flake out (what happens exactly)? Can you post any pictures of the physical test bed and the communications dialog? 1-wire errors should result in 185 or -196 degree results.

Trusted Member
Joined: 2 years ago
Posts: 52
July 3, 2020 8:34 am  

Sorry for the delay in answering.

I swapped out to a different style of ESP32 and everything is working well now.

So I think my old ESP32 dev boards are screwed. I ended up having problems clearing one board to start from scratch so perhaps the flash chip is starting to misbehave.

Eminent Member
Joined: 3 years ago
Posts: 28
July 10, 2020 11:20 am  

Depending on the number of sensors and run length, you might want to power the sensors with 5V instead of 3v3

Trusted Member
Joined: 2 years ago
Posts: 52
July 13, 2020 11:32 pm  

I generally only have one sensor and things seem to be behaving now running from 3V.

I'll keep the 5V in mind though if I have more problems