Temperature Processing Module

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Introduction

Temperature Processing Module: MT-DS

MT-DS is a temperature processing module designed for Dallas Temperature Sensors. This module works as a bridge between Dragino MS12 and Dallas/Maxim Onewire temperature sensors. it read temperature from Dallas Temp Sensors and send it to Dragino via UART port. Dragino MS12 will forward the temp info to remote server.

Features

  • Support devices:
    • DS18B20
    • DS1822
    • DS1820
  • Use ATmega168-20au MCU.
  • Show Sensor ID + Temp pairs as result.
  • Support 8 OneWire buses (with pull up 4.7K Ohm resister) and up to 80 Dallas Temp Sensors in a single Dragino.
  • Provide 5V power and GND to Dallas Temp Sensors.
  • Auto-detect new added sensors or removed sensors.
  • Remote upgrade via internet.
  • Compatible with Arduino IDE for easy debug.
  • Completely open source in both software and hardware, free to modify and change.

How to use this module

Pin out when MT-DS is installed

Pin out when MT-DS is installed

1-Wire protocol and Dallas Temperature Sensors

1-Wire bus system is designed by Dallas Semiconductor Corp. In the 1-Wire protocol. It uses a single signal line to do data transmit, receive and provide power (parasitic) to 1-Wire devices. 1-wire protocol makes it very easy for MCU to communicate with 1-wire devices.

Dallas DS18B20 is a typical 1-wire temperature sensor. It connects to MT-DS via 1-wire bus. Each DS18B20 has a unique ID and multiple sensors can be connect to the same 1-Wire bus.

More information about 1-wire protocol and Dallas Temperature Sensors please see: More info

Configuration Example

First, install the MT-DS into Dragino MS12. The MS12 will now provide totally 8 1-Wire bus. They are available at the port 1+, 1-, 2+, 2-, 3+, 3-, 4+, 4- . It also provides a 5V power at port 6a and provides GND at 6b. Choose any 1-wire bus and VCC and GND connect to the DS18B20 as shown below:

Installation of Dragino, MT-DS, and DS18B20 chip.

For easy installation and use, a 1-wire devices converter (AODC) can be used. Each AODC provides 10 3.5mm audio jacks, plug in temperature sensors with 3.5mm audio connector (ATDS-35) will simply finished all connection work.

Installation of MT-DS, AODC and Dallas Sensors


Second, Setup FTP server to get sensor data. More info about how to set up FTP server please search in the internet. here we assume a FTP server account already set up with below info:

FTP server address: 192.168.1.101
username: dragino
password: draginopass


Third, configure MS12 to send data to FTP server power on and log in MS12. go to sensor page and set up:

Pass through temperature value to server
  • save data to local file.
  • enable transparent mode: MS12 will pass through all data get from UART port to the server
  • update data to IoT server use below script:
cp /var/log/sensor.log sensor.log.tmp; curl -T sensor.log.tmp ftp://192.168.1.101 --user dragino:draginopass

After doing above, MS12 will sends the temperautre value to your FTP server. as below, the format shown is : time Sensor ID; Sensor Value(in Celsius).

Temperature Records: Time ID;Value(in Celsius);

There are different ways to update data to a remote server. more info , please consult update data to remote server

Version Info

Hardware / Software Source

Schematic , Layout and AVR source code of MT-DS can be found at

http://svn.dragino.com/examples/MT-DS

Ordering Info

Model Description Photo
MT-DS-P Temperature processing module MT-DS raw1.png
AODC 1-wire devices converter AODC Small.png
ATDS-35 DS18B20 sensors with audio connector, 3m , shielded ATDS-35 1.png

Feedback and Suggestions

Feel free to send comments or suggestions to Dragino team: info@dragino.com. We will reply you as soon as possible.

Reference Link

[1]About Onewire protocol used in Arduino : http://www.arduino.cc/playground/Learning/OneWire

[2]Arduino library for Dallas Onewire temperature sensor: http://www.arduino.cc/playground/Learning/OneWire

[3]Idea provided by EFFCONTROL.jpg