Von Neumann Architecture
Main
Memory
Main
Memory
Output
Devices
Input
Devices
Backing
Storage
Main Memory
Main memory (primary memory) is held on chips
Backing storage is not main memory
Backing storage is sometimes ...
Main Memory
Main Memory
11110011 11110011
Address
00000000
00000001
00000010
00000011
00000100
00000101
00000110
00000111
...
Main Memory
Main Memory
11110011 11110011
Address
00000000
00000001
00000010
00000011
00000100
00000101
00000110
00000111
...
Main Memory
Main Memory
11110011 11110011
Address
00000000
00000001
00000010
00000011
00000100
00000101
00000110
00000111
...
Random Access Memory
RAM
•When a program is loaded from disk its instructions are stored in the
computer’s RAM
•RAM also s...
Read Only Memory
ROM
•Has contents which are fixed when the chip is
manufactured – cannot be changed or written to
•Holds ...
National 5 Computing Science - Memory
of 8

National 5 Computing Science - Memory

National 5 Computing Science Memory
Published on: Mar 3, 2016
Published in: Education      
Source: www.slideshare.net


Transcripts - National 5 Computing Science - Memory

  • 1. Von Neumann Architecture Main Memory Main Memory Output Devices Input Devices Backing Storage
  • 2. Main Memory Main memory (primary memory) is held on chips Backing storage is not main memory Backing storage is sometimes called secondary memory
  • 3. Main Memory Main Memory 11110011 11110011 Address 00000000 00000001 00000010 00000011 00000100 00000101 00000110 00000111 00001000 00001001 Main memory consists of storage locations which are identified by unique addresses
  • 4. Main Memory Main Memory 11110011 11110011 Address 00000000 00000001 00000010 00000011 00000100 00000101 00000110 00000111 00001000 00001001 Main memory consists of storage locations which are identified by unique addresses Each storage location holds one word (the number of bits the CPU can process in a single operation) • 8 bit computer holds 8 bits in a storage location • 16 bit computer holds 16 bits in a storage location
  • 5. Main Memory Main Memory 11110011 11110011 Address 00000000 00000001 00000010 00000011 00000100 00000101 00000110 00000111 00001000 00001001 Main memory consists of storage locations which are identified by unique addresses Each storage location holds one word (the number of bits the CPU can process in a single operation) • 8 bit computer holds 8 bits in a storage location • 16 bit computer holds 16 bits in a storage location There are two types of main memory: •Random Access Memory (RAM) •Read Only Memory (ROM)
  • 6. Random Access Memory RAM •When a program is loaded from disk its instructions are stored in the computer’s RAM •RAM also stores the program data e.g. Word document, email •Can hold the operating system •All data is lost when the computer is switched off - volatile
  • 7. Read Only Memory ROM •Has contents which are fixed when the chip is manufactured – cannot be changed or written to •Holds the bootstrap loader part of the operating system •Retains its data when the computer is switched off – non-volatile