Internal Functioning of a Computer

Internal Functioning of a Computer

1. Evolution of computer hardware

   • Parts of the computer have become smaller

2. Microprocessor (CPU)

   • Most important Integrated Circuit
   • Control Unit (CU)
     • Organizes and controls the data and its flow
   • Arithmetic Logic Unit (ALU)
     • Executes arithmetic operations
   • Interpretates and carries out the basic instructions it recieves
     • Instructions for the microprocessor:
       • Complex Instruction Set Computer (CISC)
         • Bigger capacity
       • Reduced Instruction Set Computer (RISC)
         • Faster
     • Works by clock cycles
   • Microprocessor brands
     • AMD (American Micro Devices)
     • Intel
     • Motorola
     • VIA Technologies
     • Transmeta
   • Works being serial or parallel
     • Executes orders in a sequence, changing processes in microseconds
     • Executes orders simultaneously

3. Performance of microprocessors

   • Clock Speed
     • Measured in hertz or Mega/Gigahertz
     • Number of cycles (instructions executed) performed in a second
   • Cache Memory (main memory)
     • Between RAM and the processor
     • Provides the fastest acces to data
     • Primary memory (deletes when the computer is shut down)
     • Stores the most frequently requested data
     • First place where the microprocessor looks for info.
     • Up to 3 levels of cache (8kb to 9Mb of memory)
   • Size of the word
     • Number of bits a microprocessor can handle at the same time
     • 32 or 64 bits, generally

4. Compartment of the desktop

   • Circuit Cards and Storing devices
   • Power source
     • "feeds" the computer so that it can work
     • Transforms alternate current into direct current
   • Fan (cools down the computer)
   • Motherboard
     • Provides space to connect all devices to the computer
       • Many of those devices can be replaced or repaired

5. Memory

   • Random Acces Memory (RAM)
     • Primary memory (temporary)(ereases when we turn off the computer)
     • Fast but small memory (Works in nanoseconds)
     • When it cannot store everything, the order passes directly to the Hard Drive, which is bigger but slower
     • Up to 16 Gb of capacity
     • Bigger RAM = faster computer
   • Read Only Memory (ROM)
     • Secondary memory (it doesn't erase)
     • Greater capacity tan RAM, but slower
     • Looks for information via revolutions
   • Complementary Metal Oxid Semiconductor (CMOS)
     • Reading and writing memory
     • Works with a battery that is charged when the computer is on
     • Registers time and date, along with characteristics of installed hardware
   • Sequence of memory: Ram, ROM
   • Flash Memory
     • Reading and Writing Memory
     • Holds data when computer is off
     • Most expensive one
     • Mainly used in:
       • Cellphones
       • Digital cameras
       • Printers
       • Tablets

6. Peripheal Devices

   • Devices such as mouses, keyboards, etc. connected by ports
   • Universal Serial Bus (USB)
     • Compatibility with all computers
     • Easy handling and info. saving
     • Plug and Play (PnP)
       • Recognized immediatly
   • HDMI
     • Connection to tv's, sengs 64 bits at a time
   • Flow of data from component to component by cables = BUS
     • Bus 1
       • Connects processor to the memory
     • Bus 2
       • Connects processor to Peripheal devices

7. Expansion cards

   • They give the computer the ability to control Input, Process and Output
   • They fit in expansión slots
   • They contain the ports we use to connect external devices like mouses or keyboards