Inside the computer
- 2. A simple model of the computer Main Memory Input Output Processor Devices Devices Backing Storage
- 3. The Processor Arithmetic and Logic Unit (ALU) Carries out calculations e.g. 10110011 + 11110010 ALU
- 4. The Processor Control Unit Decodes and executes instructions Manages flow of information around CPU Control ALU Unit
- 5. The Processor Registers Small number of very fast temporary Register Register storage locations which hold data Register Register Control ALU Unit
- 6. The Processor and Memory A processor looks like this
- 7. The Processor and Memory A processor looks like this and memory (RAM) looks like this
- 8. The Processor and Memory Processor speed is measured in Megahertz (MHz) A typical processor will have a speed of between 2 and 3.6 MHz BUT some computers have more than one processor
- 9. The Processor and Memory Processor speed is measured in Megahertz (MHz) A typical processor will have a speed of between 2 and 3.6 MHz BUT some computers have more than one processor RAM is measured in Gigabytes (GB) A typical computer will come with between 2GB and 8GB of RAM
- 10. Memory (RAM) Address Main Memory 1 11110011 2 00011010 3 10101101 4 00110011 5 11100000 6 7 8 9 10 Large number of storage locations which hold data and programs Each location has it’s own unique address
- 11. Memory (RAM) Address Main Memory 1 2 3 4 5 6 7 8 9 10 Known as RAM (Random Access Memory) When the computer is switched off, RAM is cleared
- 12. Processor and memory Main Memory Processor Which is why we need...
- 13. Processor, memory and backing storage Main Memory Processor Backing Storage
- 14. Backing Storage The most common form of backing storage is a hard disk drive which looks like this
- 15. Backing Storage The circular area of a hard disk (the platter) is made of magnetic material The storage space of a hard disk is measured in Gigabytes (GB) A typical computer system will come with 250GB – 1000GB of storage space
- 16. Backing Storage What other backing storage devices can you think of?
- 17. Backing Storage What other backing storage devices can you think of? Optical devices (CD-ROM / DVD-ROM) Memory cards USB Flash memory
- 18. ROM We have seen that the computer’s memory is known as RAM which stands for: Random Access Memory RAM is cleared when the computer is switched off.
- 19. ROM The computer also has special memory called ROM. This stands for: Read Only Memory ROM does not get cleared when the computer is switched off ROM contains the programs which tell the computer what to do when it is switched on
- 20. Credits S2-3 Curriculum for Excellence – Inside the Computer M. Cunningham, Forrester High School (2011) All images licenced under Creative Commons 3.0 • Intel Insides by Ryan Maclean (rcmaclean on Flickr) • Hard Disk by Jeff Kubina