pi:temperature
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Temperature sensors
18B20 (digital)
Wiring:
- Waterproof:
- Red: 3.3V
- Yellow: 4.7 k pull-up (5.1k fine) and gpio pin nominated in
/boot/config.txt - Black: ground
- Kit module:
- 1 (labelled
-): ground - 2: 3.3V
- 3 (labelled
S): 4.7k pull-up and signal
At the end of /boot/config.txt (replace 21 with pin number):
dtoverlay=w1-gpio,gpiopin=21
Save and reboot.
ls -l /sys/bus/w1/devices
Grab its address (format 28-xxxxxxxxxxx). Read the temperature with
cat /sys/bus/w1/devices/28-[address]/w1_slave
The numerical value after t= is the temperature in thousandths of a degree C.
pi/temperature.1512309556.txt.gz · Last modified: 2019/11/07 17:58 (external edit)