View source for Experiment 10: DS18B20 Temperature Sensor Experiment

*[[Basic Experiment Kits For Arduino]]
*[[Basic Experiment Kits For Raspberry Pi]]
== Arduino ==
=== Experimental Phenomenon ===
* Print the detected temperature value via serial port.

=== Circuit Connection ===
*[[File:实验十：DS18B20温度传感器实验_接线.png|800px]]

=== Installing Libraries ===
*'''Installing DallasTemperature'''
**Go to Tools -> Manage Libraries, search for DallasTemperature, and click Install.
**[[File:Arduino实验十一：DS18B20温度传感器实验_安装库1.png|800px]]
*'''Installing OneWire'''
**Go to Tools -> Manage Libraries, search for OneWire, and click Install.
**[[File:Arduino实验十一：DS18B20温度传感器实验_安装库2.png|800px]]

=== Reference Program ===
<pre>
#include <OneWire.h>
#include <DallasTemperature.h>

#define ONE_WIRE_BUS 2
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

void setup(void)
{
  Serial.begin(9600);
  Serial.println("Dallas Temperature IC Control Library Demo");

  sensors.begin();
}

void loop(void)
{
  Serial.print(" Requesting temperatures...");
  sensors.requestTemperatures();
  Serial.println("DONE");

  Serial.print("Temperature for Device 1 is: ");
  Serial.print(sensors.getTempCByIndex(0));  
  
  delay(500);
}</pre>

== Raspberry Pi ==
=== Circuit Connection ===
*[[File:实验十：DS18B20温度传感器实验_接线说明.png|400px]]

=== Program Execution ===
==== Python ====
* Install the gpiozero library
**You can install the library using the following commands:
<pre>
sudo apt update
sudo apt install python3-gpiozero
</pre>
:*For other systems on Raspberry Pi, you can install the library using the following command:
<pre>
sudo pip3 install gpiozero
</pre>
:*Run the following command to view the GPIO pin definitions on the Raspberry Pi:
<pre>
pinout
</pre>
*Related Configuration
**Enable the 1-Wire bus
<pre>
sudo raspi-config
Select Interfaces oOptions -> 1-Wire -> Would you like the one-wire interface to be enabled? Select Yes -> “The one-wire interface is enabled” Select Yes -> Select finish 
</pre>
:*Restart the Raspberry Pi system
<pre>
sudo reboot
</pre>
:*Install device drivers and verify if the device is working
<pre>
sudo modprobe w1-gpio
sudo modprobe w1-therm
cd /sys/bus/w1/devices/
ls
</pre>
::*[[File:实验十：DS18B20温度传感器实验_1.png|800px]]
::*28-0000004145bb is the serial number of an external temperature sensor device, but it may vary for each device. The serial number of the DS18B20 temperature sensor is unique.
::*Note: Remember the device serial number as it needs to be modified accordingly in the program.
:*Check the current temperature
<pre>
cd 28-0000004145bb
ls
</pre>
::*[[File:实验十：DS18B20温度传感器实验_2.png|800px]]
:*View device data
<pre>
cat w1_slave
</pre>
::*[[File:实验十：DS18B20温度传感器实验_3.png|800px]]
::*The second line t=24437 represents the current temperature value. To convert it to Celsius, divide by 1000, so the current temperature = 24437/1000 = 24.44°C.
*Download the Raspberry Pi reference example, unzip the file, and copy it to the user directory.
**Modify the project file: Open the corresponding file raspberrypi/10/python_gpiozero/sensor.py
***Change the fifth line DS18B20 = '28-0000004145bb' to the device address queried above, and then save the file.
***[[File:实验十：DS18B20温度传感器实验_4.png|800px]]
**Run
<pre>
cd raspberrypi/10/python_gpiozero
python sensor.py
</pre>
*You will see the Raspberry Pi correctly running the DS18B20 program, continuously printing the detected temperature values. To exit, press ctrl+C.
*For more commands, please refer to the [https://gpiozero.readthedocs.io/en/latest/installing.html gpiozero documentation]

== Example Download ==
* [[:File:Basic Experiment Kits For Arduino.zip|Arduino Example Programs]]
* [[:File:Basic Experiment Kits For Raspberry Pi.zip|Raspberry Pi 5 Example Programs in Python]]

== Related Examples ==
{{Arduino and Raspberry Pi Case}}