Revision as of 08:00, 30 September 2012

Introduction

一个MT-DS模块的单独图片

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

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:

一个接线端子的图，示意接口的一个面包板的连接图，示意到DS18B20的连接。

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 will simply finished all connection work.

Dragino 连接 AODC的示意图。

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:

• 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).

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

Feedback and Suggestions

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

Reference Link

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

use Arduino library designed for Dallas Onewire temperature sensor: http://www.arduino.cc/playground/Learning/OneWire