Chapter 1 C++

In this chapter we will learn about hardware and software. (easy I know). Data Hierachy, Computer Organization, Machine, Assembly and High-level languages. Intro to object oreniented technology, OS, Programming languages, C++ dev enviroment. Testing applications, web 2.0, Future C++:TR1, the new C++ standard. Keeping up to date. Wrap-up.


Lets get started: Damn that was a lot to type.


First we need to point out that the software makes the hardware work.
Software is all around us in our phones(we will talk about this later on OS). Computers, Iphone apps and GPS. So what is a computer? A computer is just a device that can calculate operations and make logical decisions much faster than humans can.A computer can preform more calculations in one second than a human can in one lifetime. For further information about this I recommend a video: https://www.youtube.com/watch?v=9a7XQmEBK5Q


This is a great video for understanding inputs and outputs for switches and gates. Gates are for operations. And ----> output----> Or ---> Not
more than likely we won't work with transistors, but it is a good example for the way we can see the operations in real time. This is a big long process of confusing math 1's and 0's or binary. Look up a youtube video on binary code.


Programs
Computers run instructions and process data from computer program built by you the programmer.
Evolution
The evolotion of computers is phenominal at one point we had computers that filled entire rooms. Take a look at some of the technology on Star-trek notice the communicator (cell phone much?). Anyway we got off track now we have mini computers like the Rasberry pi, Android mini pc. Right now you can buy both of these for under 50 dollars. Silicone is one of the most abundant pieces of material out there it is made from sand people. Come on sand?


Computer chips(silicone- Microprocessors) are in the heart of everything game controllers, anti-lock breaks in cars, navagation systems.


Moores Law
Ok this is not a very hard law like the robot laws it is as simple as this.
Bill: "Hey do you remember when they made 520mb flash drives."
Bob: "That was a few years ago the lowest one i got is 8gb."
Bill:"Yeah I remember paying 35 dollars for a 1 gb usb flashdrive."
Bob: "Yeah we got ripped off"
Bill: "Yeah Moore really screwed us."
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end scene
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Ok so while the two programmer twins(bill and bob) are off getting lunch we will make sense of what they where talking about. Moores law of course the capabilities of information systems improve but get cheaper. Older computers get outdated quickly. (That is when you put DSL on them). I recently put DSL(Damn small Linux) On a older 1998 computer. It became as functional as a newish netbook. See my notes on linux if you need help with instalation.


Data Hiearchy--Just google it I will say think of it this way we have bytes, bits, files and memory items.



Logical Units


Logical unit | Description
Input unit - This “receiving” section obtains information (data and computer programs) from input devices and places it at the disposal of the other units for processing. Most information is entered into computers through keyboards, touch screens and mouse devices. Other forms of input include speaking to your computer, scanning images and barcodes, reading from secondary storage devices (like hard drives, DVD drives, Blu-ray DiscTM drives and USB flash drives—also called “thumb drives” or “memory sticks”), receiving video from a webcam andhaving your computer receive information from the Internet (such as when you download videos from YouTubeTM or e-books from Amazon). Newer forms of input include reading position data from a GPS device, and motion and orietation information from an accelerometer in a smartphone or game controller.
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Output unit - This “shipping” section takes information that the computer has processed and places it on various output devices to make it available for use outside the computer. Most information that’s output from computers today is displayed on screens, printed on paper, played as audio or video on portable media players (such as Apple’s popular iPods) and giant screens in sports stadiums,transmitted over the Internet or used to control other devices, such as robots and “intelligent” appliances.
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Memory unit -This rapid-access, relatively low-capacity “warehouse” section retains
information that has been entered through the input unit, making it immediately available for processing when needed. The memory unit also retains processed information until it can be placed on output devices by the output unit. Information in the memory unit is volatile—it’s typically lost when the computer’s power is turned off. The memory unit is often called either memory or primary memory. Typical main memories on desktop and notebook computers contain between 1 GB and 8 GB (GB stands for gigabytes; a gigabyte is approximately one billion bytes).
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Arithmetic This “manufacturing” section performs calculations, such as addition, subtrac-
and logic unit tion, multiplication and division. It also contains the decision mechanisms
(ALU) that allow the computer, for example, to compare two items from the memory unit to determine whether they’re equal. In today’s systems, the ALU is usually implemented as part of the next logical unit, the CPU.
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Central Processor Unit- This “administrative” section coordinates and supervises the operation of the processing other sections. The CPU tells the input unit when information should be read unit (CPU) into the memory unit, tells the ALU when information from the memory unit should be used in calculations and tells the output unit when to send information from the memory unit to certain output devices. Many of today’s computers have multiple CPUs and, hence, can perform many operations simultaneously. A multi-core processor implements multiple processors on a single integrated-circuit chip—a dual-core processor has two CPUs and a quad core processor has four CPUs. Today’s desktop computers have processors that can execute billions of instructions per second.
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Secondary Storage This is the long-term, high-capacity “warehousing” section. Programs or data storage unit not actively being used by the other units normally are placed on secondary drive untill they are needed later.


(Dietel & Dietel, Chapter 1.4, 2012).









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