Mar 112016
 


Apple, the producer of the revolutionary products like iPhone, iMac, iPad and iPod, is the second richest apple logocompany of the world and the most valuable brand of the world. By giving the market its innovative products, it has been successful to create history in terms of revenue and profit in corporate world.

In this post, we will let you know about the 10 interesting facts about Apple, that you may or may not know:

  1. In every minute, Apple earns 3 hundred thousand US Dollars. This amount is even greater than the transactions of the whole stock market of Russia.
  2. Apple owns more cash in hand than that owned by the US Government.
  3. There are 80 thousand Apple employees worldwide.
  4. According to probability analysis, the probability of getting admission at Harvard University is found to be greater than the probability of getting a job at Apple Store.
  5. Within the first 3 months of 2014, Apple alone had earned the amount equal to the total revenues of Google, Facebook and Amazon combined.
  6. Smoking near an Apple computer voids the warranty of the device.
  7. In every advertisement of iPhone, the time displayed on the screen of the phone is 9:41AM. This time has a special meaning. In 2007, when the ‘then CEO’, Steve Jobs, had launched the first ever iPhone, the time was 9:41AM.
  8. When the prototype of the first ever iPod was presented to Steve Jobs, he had thrown it into water. He hadn’t done so because he disliked the prototype or because of anger but to see if the device can be made more compact or not.
  9. Whatever you say to Siri first goes to Apple. It is stored only after it has been analyzed properly.
  10. Samsung is the manufacturer of the ‘Retina Display’ of Apple iPad. This display is the most expensive part of iPad.



Mar 102016
 


processorperi

The data bus, address bus and control bus that arise out of the processor and are intended to communicate with I/O devices are called I/O bus. The communication link between the processor and several peripherals is shown in the given figure. The I/O bus is connected to all peripheral interfaces. To communicate with a particular device, the processor places a device address on the address bus. Each interface attached to the I/O bus contains an address decoder that monitors the address lines. When the interface detects an address to be its own, it activates the path between the bus and the device that it controls. All other peripherals are disabled. At the same time, a function code is provided to the control bus which is called I/O command. The types of I/O commands that are given out by the processor are:

  1. Control Commands: This is the function code that activates the corresponding peripherals and informs them about what to do.
  2. Status Commands: A status command is used to test various status conditions in the interface and the peripheral devices like BUSY, ERROR, data available or not in the buffer etc .
  3. Data Output Command: A data output command causes the interface to respond by transferring the data from the processor to the peripheral. The data is sent from the CPU to the buffer of interface after this command is provided.
  4. Data Input Command: This command is sent by the CPU if the data is to be read from the peripheral. After this command is issued, the data of peripheral are extracted into the buffer of the interface and are read by the CPU.