1.1 System Architecture with additions

1.1 System Architecture with additions

1. Processor

   • "brains of the computer"
   • processes data
   • executes (carries out) instructions
   • proccessors have a clock speed,cache and core
     • these are measured in hertz
       • there are GHz, MHz and just Hz
         • these are the number of cycles per second
           • 1 GHz=1 billion cycles a second
             • 1 MHz= 1 million cycles a second
   • Cores
     • you also have multi cores!
       • dual core=twice as many instructions at once
         • quad core quadruples the amount of instructions at once
   • Cache
     • located closer to the processor than the ram so it can do instructions quicker than going to the ram of the computer
   • An instruction tells the computer what to do
   • increasing the cache size will reduce the memory to disk transfers
     • as it will speed up processing these instructions.
   • each processor has a core

2. Embedded systems

   • is a computer inside another object or device
     • e.g. A dishwasher
   • it cannot be another computer that it is within
     • IT IS A COMPUTER WITHIN A DIFFERENT DEVICE
   • does not have an operating system
   • used for specialised tasks
     • These devices range from household to industrial.

3. I/O (Input/Output)

   • Computers can have inputs and outputs these are also known a peripherals it does not need these to run!
   • e.g. keyboard or mouse.

4. Buses

   • Data bus
     • Bi-Directional
     • data can be read and written
   • Address bus
     • Uni-directional
     • processes a given address

5. secondary storage

   • hard disks,usb sticks or sd carsd

6. control bus

   • sends controls given by the processor

7. F.D.E (fetch,decode then execute