System Architecture

System Architecture

1. CPU

   • process
     • fetch
     • decode
     • execute
   • ALU
     • calculations
     • logical decsions
   • control unit
     • controls flow of data
   • register
     • high - speed memory
     • data/instructions being processed

2. Memory

   • cache
     • level 1
       • low storage
       • fast access
     • level 3
       • high storage
       • slow access
     • frequent instructions
   • RAM
     • volatile
       • lost when turned off
     • Virtual memory
       • RAM full
       • used until RAM has enough space
     • instructions currently in use
     • larger than ROM
   • ROM
     • non-volatile
       • stays when turned off
     • boot-up
     • firmware
       • BIOS
       • can't be changed
   • Flash memory
     • can be erased and re-written
     • long - term storage
       • SD card
       • USB

3. CPU improvements

   • clock-speed
     • increase
     • cycles per second
     • Hz
   • increase cache
     • less memory accessed from RAM
   • more cores
     • more FDE cycles