Hardware

Hardware

1. Architecture (Von Neumann)

2. Architecture (continued)

   • CISC
     • Has complex operations (multiple steps at once)
     • Physically larger
     • Can execute complex operations very quickly
     • The processors in PCs are CISC
   • RISC
     • Smaller instruction set and single step instructions
     • Slower than CISC (multiple instructions needed)
     • Use less power and are cheaper that CISC
     • Less heat than CISC and physically smaller
     • Processors used in smartphones are RISC

3. CPU Speed

   • Clock Speed
     • The faster the clock speed, the more instructions can be fetched a second
     • More power is needed for higher clock speeds, leads to more heat
     • It's measured in Gigahertz (GHz)
   • Number of Cores
     • A core is a complete CPU, with its own Von Neumann Architecture
     • Several instructions can be fetched and executed at the same time
     • Limited by instructions that must be executed in an order
   • Cache Size
     • Very fast, stores frequently used instructions
     • The more cache, the better the performance, so less instructions in RAM

4. Additional Components

5. Embedded Systems

   • They're small, dedicated computers on a single chip, embedded in devices such as: washing machines, engine sensors and house alarms
   • Instructions are held in ROM or flash memory
   • Produced for a single purpose unlike desktop PCs or smartphones

6. Units

   • Data is stored as 1s and 0s (on and off)
   • There are 8 bits in a byte
   • A CD can store 800MB A DVD can store around 4.7GB
   • Magnetic hard disks can store up to 5TB MicroSD cards can store up to 500GB

7. Input & Output Devices

   • Input - Transfer data from the user to the computer
   • Output - Transfer data from the computer to the user
   • Input - Keyboard, Mouse, Microphone, Camera
   • Output - Screen, Speaker, Printer

8. Primary & Secondary Storage