Raspberry Pi LM75BIMM Temperature Sensor Java Tutorial

LM75BIMM is a digital temperature sensor incorporated with thermal watchdog and has two wire interface which supports its operation upto 400 kHz. It has an over temperature output with programmable limit and hystersis. Here is the demonstration with a java code using Raspberry Pi.

1. Raspberry Pi

2. LM75BIMM

3. I²C Cable

4. I²C Shield for Raspberry Pi

5. Ethernet Cable

Take a I2C shield for raspberry pi and gently push it over the gpio pins of raspberry pi.

Then connect the one end of I2C cable to LM75BIMM sensor and the other end to the I2C shield.

Also connect the Ethernet cable to the pi or you can use a WiFi module.

Connections are shown in the picture above.

The java code for LM75BIMM can be downloaded from our github repository- Dcube Store

Here is the link for the same :

https://github.com/DcubeTechVentures/LM75BIMM/blob/master/Java/LM75BIMM.java

We have used pi4j library for java code, the steps to install pi4j on raspberry pi is described here:

http://pi4j.com/install.html

You can also copy the code from here, it is given as follows:

// Distributed with a free-will license.

// Use it any way you want, profit or free, provided it fits in the licenses of its associated works.

// LM75BIMM

// This code is designed to work with the LM75BIMM_I2CS I2C Mini Module.

import com.pi4j.io.i2c.I2CBus;

import com.pi4j.io.i2c.I2CDevice;

import com.pi4j.io.i2c.I2CFactory;

import java.io.IOException;

public class LM75BIMM

{

public static void main(String args[]) throws Exception

{

// Create I2C bus

I2CBus Bus = I2CFactory.getInstance(I2CBus.BUS_1);

// Get I2C device, LM75BIMM I2C address is 0x49(73)

I2CDevice device = Bus.getDevice(0x49);

// Select configuration register

// Continuous conversion mode, normal operation

device.write(0x01, (byte)0x00);

Thread.sleep(500);

// Read 2 bytes of data from address 0x00(0)

// temp msb, temp lsb

byte[] data = new byte[2];

device.read(0x00, data, 0, 2);

// Convert the data to 9-bits

int temp = ((data[0] & 0xFF) * 256 + (data[1] & 0x80)) / 128;

if(temp > 255)

{

temp -= 512;

}

double cTemp = temp * 0.5;

double fTemp = cTemp * 1.8 + 32;

// Output data to screen

System.out.printf("Temperature in Celsisus : %.2f C %n", cTemp);

System.out.printf("Temperature in Fahrenheit : %.2f F %n", fTemp);

}

}

LM75BIMM is ideal for a number of applications including base stations, electronic test equipment, office electronics, personal computers or any other system where temperature monitoring is critical to performance. Therefore, this sensor has a pivotal role in many of the highly temperature sensitive systems.