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I'm starting work on a fermentation monitor using the Adafruit temperature sensing tutorial, a RPi B+ running Raspbian, a 4.7 kOhm resistor and a DS18B20 to which I've soldered male breadboard pins. After wiring exactly as the tutorial states (on multiple breadboards), I do:

sudo modprobe w1-gpio
sudo modprobe w1-therm
ls /sys/bus/w1/devices

But I only get a folder named "w1_bus_master1"; no 28-xxx folders. I understand this is a common question, so here is what I have done so far:

  • This DS18B20 has worked (and still works) when connected to my Arduino, so the sensor is not faulty.

  • Tried connecting the sensor to the 5V GPIO with no success.

  • Tried wiring the resistor as it is on my Arduino's breadboard, with the power/data/ground on one column, the power/data resistor on the next column, and the sensor pins on the column after that; no luck.

  • Tried using the same wiring on multiple breadboards.

Any ideas where I'm going wrong?

A picture of the connections.

  • 1
    A photo and a precise description of the connections between the Pi and sensor (including the resistor connections) may be useful. – joan Jan 8 '15 at 10:00
  • As far as I can tell the connections seem correct. Ground - Ground, 3V3 - Power, gpio 4 - data, data pulled up to 3V3 via resistor. – joan Jan 8 '15 at 14:03
  • I've just set one up and it works fine. The obvious error is swapping the ground and power connections. – joan Jan 8 '15 at 14:26
  • What version are running? In the terminal type uname -a – user26736 Feb 6 '15 at 19:39
  • Related: DS18b20 temperature sensor not listed. – Ruslan Nov 19 '17 at 19:25
28

Found it!

sudo nano /boot/config.txt

add :

dtoverlay=w1-gpio

this has to do with kernel update, find more info in this link

  • Welcome to Raspberry Pi! Whilst this may theoretically answer the question, it would be preferable to include the essential parts of the answer here, and provide the link for reference. – Steve Robillard Feb 11 '15 at 21:35
  • Hell yeah! I was really struggling with this! I had a working Pi2 with a 10-probe 1-wire network. I made a new network with a Pi3 and couldn't get it to work even with the sensor cluster from the old Pi2. If I could give you more than +1 I would. Thanks, this worked a charm! – Jim Aug 28 '17 at 6:45

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