Electronics Tutorials and Technalogy Updates: Electronics And Engineering Tutorials

What is AJAX ? An Introdution for Beginners

How to develop Web Applications with AJAX

AJAX stands for Asynchronous Javascript And XML, although it also works synchronously and without XML, but these to things makes a great communication technique that can work on back end without disturbing the whole web Page. Before AJAX the web applications were limited because of the fact that to retrieve the new data from server the whole page had to be reloaded, it was time consuming and somewhat annoying. There are many websites that wouldn't be working without it, let's take an example ofFacebook the popular social networking site, if a person has a facebook account and he logs in his time line will be displayed, what if his whole 2-year time line is displayed that will be very resource consuming and buttons on the page end would be annoying. Here comes the AJAX to rescue such that when a user reaches the end of the current page javascript detects it sends a back end serve request to retrieve some more data without refreshing the page, serve responds to it and send back the data and .....

Now lets see two examples first with javascript-XML and other with javascript-PHP/MySQL :

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USB 2.0 Architecture For Programming Microcontrollers

Programming USB Peripheral in Microcontrollers:

Introduction:

USB stands for "Universal Serial Bus", as the name suggests its a communication bus that can be used for the tranfer any data between different embedded systems like PCs, Cell Phones, Cameras etc.
If we talk about history we would see that the USB Protocol is a revolutionised version of different communication protocols like Serial Transmission(UART-USART) or Parallel transmission using parallel port etc. All of these communication protocols had some drawbacks and limitations e.g Speed, ability to host a device, supporting multiple devices at the same time..., so a univesal protocol had to be developed that can handle all this limits or conflicts and that universal protcol is called USB.

Architecure:

USb 2.0 ports come indifferent configurations as shown in fig.1, all of which have 4 pins but the size is different you can choose any one of them depending on the need of your embedded system.

Developing Star Rating widget

Star rating widget is an important part of many entertainment and educational websites like IMDB or Freebooksdownload and many more. It gives an attractive method for the people to engage. Today we are going to see the simplest method to create a CSS Star widget and then using javascript and forms togather to retrieve information from it.

The markup uses the unicode entity for a star (☆) right in it. If you have a UTF-8 charset that should be no big deal. Alternatively you could use ☆. You could use as many stars as you like depending upon your need as follows: