EP-0031
- Raspberry Pi LM75B Temperature Sensor v1.0 SKU:EP-0031
Product Feature
*9bit high resolution ADC in chip *Temperature resolution of 0.125°C. *I2C bus plug and play *Compatible with all kind of development board.
Compatibility List
- Compatibility {| class="wikitable" style="text-align: center;" |- !Platform !!LM75B temperature Sensor Version 1.0!! Notes |- |Raspberry Pi 3 Model B Plus|| WIP || WIP: work in process |- |Raspberry Pi zero || √|| |- | Raspberry Pi zero W || √|| |- |Raspberry Pi 3 Model B|| √|| |- |Raspberry Pi 2 Model B|| √|| |- |Raspberry Pi Model B+|| √|| |- |}
Port
*Raspberry Pi GPIO pins
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Product Parameters
*Working voltage: 1.8V-5.5V, accuracy can be up to 0.5 when working voltage is higher than 3v. *Temperatures range from−55°C to +125°C *Supply current of 3.5µA in shutdown mode for power conservation *Temperature accuracy of: ±2°C from−25°C to +100°C *Temperature accuracy of: ±3°C from−55°C to +125°C
Package Include:
- 1 x Raspberry Pi LM75B Temperature Sensor v1.0
Typical Application
*Industrial controllers *Environmental monitoring *Smart home *Interactive devices
How to wire it up
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How to use it
*i2c-tools package is required, so you should install it before you get temperature as following command:
sudo apt-get update && sudo apt-get -y install i2c-tools
*Enable I2c function by editing /boot/config.txt,make sure it contain this two parameter as following:
device_tree=bcm2710-rpi-3-b.dtb
dtparam=i2c_arm=on
**Or you can use this command to enable I2C:
sudo raspi-config
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**Select as this picture, then you can enable I2C easily.
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*Please Remember to reboot your Raspberry Pi.
*After rebooting, please open a terminal and input this command to get temperature:
i2cget -y 1 0x48 0x00 w |awk '{printf("%0.1f C\n",(a=((("0x"substr($1,5,2)substr($1,3,1))*0.0625)+0.1) )>128?a-256:a)}'
Result:
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Examples
*Shell scripts:
You can create a file called lm75.sh and edit as following:
#!/bin/bash
while true
do
i2cget -y 1 0x48 0x00 w | awk '{printf("%.1f C.\n", (a=((("0x"substr($1,5,2)substr($1,3,1))*0.0625)+0.1) )>128?a-256:a)}'
sleep 1
done
and set an execute right to this file:
chmod +x lm75.sh && bash lm75.sh
*C code: You can login to your Raspberry Pi and open a terminal, and then download the zip package from this link below: [File:LM75_C.tar.gz.zip ](/docs/File:LM75_C.tar.gz.zip )
unzip it and compile it.
unzip LM75_C.tar.gz.zip
tar -xf LM75_C.tar.gz
cd LM75_C/
make
./test.o
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---- *Python running in command line:
**If you want to use python to drive this sensor, you have to install this two packages first.
sudo apt-get update
sudo apt-get install -y python-smbus python-scipy
**Create a file called LM75.py as below:
import time import smbus LM75_ADDRESS = 0x48 LM75_TEMP_REGISTER = 0 LM75_CONF_REGISTER = 1 LM75_THYST_REGISTER = 2 LM75_TOS_REGISTER = 3 LM75_CONF_SHUTDOWN = 0 LM75_CONF_OS_COMP_INT = 1 LM75_CONF_OS_POL = 2 LM75_CONF_OS_F_QUE = 3 class LM75(object): def (self, mode=LM75_CONF_OS_COMP_INT, address=LM75_ADDRESS, busnum=1): self._mode = mode self._address = address self._bus = smbus.SMBus(busnum) def regdata2float (self, regdata): return (regdata / 32.0) / 8.0 def toFah(self, temp): return (temp * (9.0/5.0)) + 32.0 def getTemp(self): raw = self._bus.read_word_data(self._address, LM75_TEMP_REGISTER) & 0xFFFF raw = ((raw << 8) & 0xFF00) + (raw >> 8) return self.toFah(self.regdata2float(raw))
and then create another file called test.py:
import LM75 sensor = LM75.LM75() print sensor.getTemp()
**execute by this command:
