876 Lady's First Tapeout
876 : Lady's First Tapeout
- Author: Lady Nicole Payan Cepeda
- Description: 4-bit comparator.
- GitHub repository
- Open in 3D viewer
- View in Wokwi
- Clock: 0 Hz
How it works
This project is a 4-bit comparator. It compares 2 binary numbers A and B using logic gates to determine if:
-A = B -A > B -A < B
The comparator checks the bits from the (Most significant bit) MSB to the (Least significant Bit) LSB. MSB LSB MSB LSB IN0 IN1 IN2 IN3 IN4 IN5 IN6 IN7
The comparator controls the 7-segment display to show a letter representing the result of the comparison: -If A=B, E for Equal displayed -If A>B, H for High is displayed -If A=B, L for Low is displayed
The display segments are controlled using OR logic gates so only one signal drives the display.
How to test
Set the two 4-bit inputs (A and B) to different binary values and observe the 7-segment display output.
| A (4-bit) | B (4-bit) | Expected Result | Displayed Letter|
| IN0 to IN3 | IN4 to IN7 | ||
|---|---|---|---|
| 0000 | 0000 | A = B | E |
| 0011 | 0011 | A = B | E |
| 1000 | 0111 | A > B | H |
| 1111 | 0001 | A > B | H |
| 0010 | 0100 | A < B | L |
| 0001 | 1000 | A < B | L |
External hardware
- 7-segment display for output visualization
- Input switches or digital inputs for the two 4-bit values (A and B)
No additional external hardware is required.
IO
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | input number a MSB | ouptut display | |
| 1 | input number a | ouptut display | |
| 2 | input number a | ouptut display | |
| 3 | input number a LSB | ouptut display | |
| 4 | input number b MSB | ouptut display | |
| 5 | input number b | ouptut display | |
| 6 | input number b | ouptut display | |
| 7 | input number b LSB | ouptut display |