A bank security system activates an alarm when the master switch is armed (M=1M = 1M=1) and motion is detected (S=1S = 1S=1), OR if the manual panic button is pressed (P=1P = 1P=1) at any time.
Table 1 shows the truth table for this alarm system with inputs:
- M (Master Switch: 0 = Off, 1 = Armed)
- S (Motion Sensor: 0 = Clear, 1 = Detected)
- P (Panic Button: 0 = Not pressed, 1 = Pressed)
- Output A (Alarm: 0 = Quiet, 1 = Sounding)
Table 1
| Master Switch (M) | Motion Sensor (S) | Panic Button (P) | Alarm (A) |
|---|---|---|---|
| 0 | 0 | 0 | 0 |
| 0 | 0 | 1 | 1 |
| 0 | 1 | 0 | 0 |
| 0 | 1 | 1 | 1 |
| 1 | 0 | 0 | 0 |
| 1 | 0 | 1 | 1 |
| 1 | 1 | 0 | 1 |
| 1 | 1 | 1 | 1 |
Draw the logic circuit that represents the truth table in Table 1. You must use standard symbols for logic gates.
Boolean logic Questions
Practise AQA GCSE Computer Science Boolean logic with exam-style questions for GCSE Computer Science. 83 questions, matched to the AQA GCSE Computer Science (8525) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.