3.4 Computer Systems
Focus
3.4 focuses on computer systems. This will cover topics such as operating system, boolean logic, software classification and system architecture. Click on the links above to navigate to specific sections you wish to revise. Each topic should have some reading material, video, exam questions as well as some exemplar answers.
Logic gate
The tables below highlight the truth table for the different gates:
AND (both inputs have to be on)
| A | B | Q |
| 0 | 0 | 0 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 1 |
OR (Only one input needs to be on)
| A | B | Q |
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 1 |
NOT (This is the inverse of an input)
| A | Q |
| 0 | 1 |
| 1 | 0 |
Use the logic gate simulator below to create circuits using a combination of OR, AND as well as NOT.
http://www.neuroproductions.be/logic-lab/