Introduction
In front of the stone gate, the Toucan winks at you:
“Remember my AND gate? Today we’re going to invert it with the help of NOT.
The gate will open unless both torches are lit.”
Logical goal
Build an output that is true except when A = 1 and B = 1:
See full truth table
| A | B | A AND B | Output = NOT(A AND B) |
|---|---|---|---|
| 0 | 0 | 0 | 1 |
| 0 | 1 | 0 | 1 |
| 1 | 0 | 0 | 1 |
| 1 | 1 | 1 | 0 |
Simulator instructions
1. Place the components
- Make sure you are in Edit mode.
- Inputs: A, B
- AND Gate
- NOT Gate
- Output
2. Connect
- A and B ➔ AND
- AND output ➔ NOT
- NOT output ➔ Output
3. Test
- Go through 00, 01, 10, 11.
- The gate opens in all cases except 11.
Victory condition: the output is 0 only when A = 1 and B = 1.
Quick tips
- If it always gives 0, you probably connected the Output to the AND instead of the NOT.
Simulator
What did you learn?
- How to negate a compound condition: first AND, then NOT.