Sunday, May 27, 2018
Wednesday, May 23, 2018
Monday, May 21, 2018
HOW TO INSTALL MQTT BROKER IN WINDOWS
1 ECLIPSE MOSQUITTO
According to its website at https://mosquitto.org/ , “Eclipse Mosquitto™ is an open source (EPL/EDL licensed) message broker that implements the MQTT protocol versions 3.1 and 3.1.1. MQTT provides a lightweight method of carrying out messaging using a publish/subscribe model.” On the following, we will discuss about how to install and test Mosquitto on Windows, Raspberry Pi and Linux System.1.1 ECLIPSE MOSQUITTO ON WINDOWS
The following steps describe how to install and run Mosquitto on Windows:
1. Download Mosquitto broker for Windows from http://www.eclipse.org/downloads/download.php?file=/mosquitto/binary/win32/mosquitto-1.4.10-install-win32.exe
2. Install Mosquitto on Windows by following the steps specified in https://sivatechworld.wordpress.com/2015/06/11/step-by-step-installing-and-configuring-mosquitto-with-windows-7/
3. To start the Mosquitto service, open up Windows command line by clicking “Start” on the Taskbar, typing in “cmd” and pressing Enter. Navigate to where you installed Mosquitto. By default it will be located in “C:\Program Files (x86)\mosquitto” as shown on the picture below.
TUTORIAL ON MOSQUITTO AND PAHO
Page 2 of 4
4. You can test your broker with the following commands on two new terminals:
Use `mosquitto_sub` to subscribe to a topic on terminal 1:
mosquitto_sub -t 'test/topic' -v
And to publish a message on terminal 2:
mosquitto_pub -t 'test/topic' -m “hello world”
REFERENCED FROM :http://www.steves-internet-guide.com/install-mosquitto-broker/
https://mosquitto.org/
Working of Refrigerator & Refrigeration Principle
Working of Refrigerator & Refrigeration Principle
The basic principle
The basic principle of refrigeration is simple. You simply pass a colder liquid continuously around the object that is to be cooled. This will take heat from the object. In the example shown, a cold liquid is passed over an apple, which is to be cooled. Due to the temperature difference, the apple loses heat to the refrigerant liquid. The refrigerant in turn is heated due to heat absorption from the apple.
It is clear that, if we can produce cold liquid refrigerant continuously, we can achieve continuous refrigeration. This simple fact forms the core of the refrigeration technology. We will next see how this is achieved.
Components of Refrigerator
1.Throttling Device
obstruct the flow of liquid. cold liquid is provided by this . throttling device is a capillary tube. It has approximate length of 2 m for effective throttling at the inlet. The refrigerant should be a high pressure. the boiling point of refrigerant is lowered and it starts to evaporate. It is wrong to say that the throttling is a process. We know only the endpoints of throttling2.Evaporator - Heat Absorption Process
This phase is simple. This cold liquid is passed over the body that has to be cooled. As a result, the refrigerant absorbs the heat.the refrigerant further evaporates and transforms in to pure vapour. A proper heat exchange is required.
3.Compressor
The compressor will raise the pressure back to its initial level. But since it is compressing gas along with pressure, temperature will also be increased. This is unavoidable.
4.Condenser
This part is fitted outside the refrigerator and the refrigerant temperature is higher than atmospheric temperature. so heat will dissipate to the surroundings. The vapor will be condensed to liquid
Sunday, May 20, 2018
What is an Arduino?
Introduction
Arduino is an open-source platform used for building electronics projects. Arduino consists of both a physical programmable circuit board (often referred to as a microcontroller) and a piece of software, or IDE (Integrated Development Environment) that runs on your computer, used to write and upload computer code to the physical board.
The Arduino platform has become quite popular with people just starting out with electronics, and for good reason. Unlike most previous programmable circuit boards, the Arduino does not need a separate piece of hardware (called a programmer) in order to load new code onto the board – you can simply use a USB cable. Additionally, the Arduino IDE uses a simplified version of C++, making it easier to learn to program. Finally, Arduino provides a standard form factor that breaks out the functions of the micro-controller into a more accessible package.
what is on the board?
Arduino Uno
The Uno is a great choice for your first Arduino. It’s got everything you need to get started, and nothing you don’t. It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a USB connection, a power jack, a reset button and more. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started.
LilyPad Arduino
This is LilyPad Arduino main board! LilyPad is a wearable e-textile technology developed by Leah Buechley and cooperatively designed by Leah and SparkFun. Each LilyPad was creatively designed with large connecting pads and a flat back to allow them to be sewn into clothing with conductive thread. The LilyPad also has its own family of input, output, power, and sensor boards that are also built specifically for e-textiles. They’re even washable!
Red Board
At SparkFun we use many Arduinos and we’re always looking for the simplest, most stable one. Each board is a bit different and no one board has everything we want – so we decided to make our own version that combines all our favorite features.
The RedBoard can be programmed over a USB Mini-B cable using the Arduino IDE. It’ll work on Windows 8 without having to change your security settings (we used signed drivers, unlike the UNO). It’s more stable due to the USB/FTDI chip we used, plus it’s completely flat on the back, making it easier to embed in your projects. Just plug in the board, select “Arduino UNO” from the board menu and you’re ready to upload code. You can power the RedBoard over USB or through the barrel jack. The on-board power regulator can handle anything from 7 to 15VDC.
reference fron :- https://learn.sparkfun.com/tutorials/what-is-an-arduino
This is LilyPad Arduino main board! LilyPad is a wearable e-textile technology developed by Leah Buechley and cooperatively designed by Leah and SparkFun. Each LilyPad was creatively designed with large connecting pads and a flat back to allow them to be sewn into clothing with conductive thread. The LilyPad also has its own family of input, output, power, and sensor boards that are also built specifically for e-textiles. They’re even washable!
At SparkFun we use many Arduinos and we’re always looking for the simplest, most stable one. Each board is a bit different and no one board has everything we want – so we decided to make our own version that combines all our favorite features.
The RedBoard can be programmed over a USB Mini-B cable using the Arduino IDE. It’ll work on Windows 8 without having to change your security settings (we used signed drivers, unlike the UNO). It’s more stable due to the USB/FTDI chip we used, plus it’s completely flat on the back, making it easier to embed in your projects. Just plug in the board, select “Arduino UNO” from the board menu and you’re ready to upload code. You can power the RedBoard over USB or through the barrel jack. The on-board power regulator can handle anything from 7 to 15VDC.
what are the state machines?
WHAT ARE THE STATE MACHINES.
INTRODUCTION:
A state
machine is any device storing the status of something at a given time. The
status of something at a given time. The status changes based on inputs,
providing the resulting output for the implemented changes. A finite state
machine has finite internal memory. Input symbols are read in a sequence
producing an output feature in the form of a user interface.
State machines are represented using state diagrams. The output of a
state machine is a function of the input and current state. State machines play
a significant role in areas such as electrical engineering.
The operation of a state machine begins from a start state. On a
successful transition it ends up in an accept state. The transition takes place
based on the inputs provided. The current state depends on the past states of
the systems. The number of states formed depends on the available states of
memory. A transition is enabled based on
certain conditions and indicates a state change. An action describes an
activity performed at the given moment. The different types of actions are
transition actions, input action, entry and text action.
Do You Know About MQTT?
what is MQTT?
MQTT == MQ Telemetry Transport
In a nutshell--->
A light weighted event and message oriented protocol allowing to asynchronously communicate efficiently across constr
ained networks to remote systems.
publish subscribe messaging protocol allowing a message to be published once multiple consumers(applications/devices) to receive the messages providing decoupling between the product and consumer(s)
A producer sends (publishes) a message (publication)on a topic(subject)
A consumer subscribes (make a subscription) for messages on a topic(subject)
A message server/broker matches publications to subcriptions
* If no matches the message is discarded
*If one or more matches the message is delivered to each matching subscriber/ consumer.
referenced from:- https://www.youtube.com/watch?v=-KNPXPmx88E
Saturday, May 19, 2018
Thursday, May 17, 2018
System architecture references
https://study.com/academy/lesson/systems-architecture-definition-characteristics.html
Saturday, May 12, 2018
Subscribe to:
Posts (Atom)