HardwareLogic Design Lab, LAU2026
Smart Attendance System
A classroom attendance machine breadboarded from 47 74LS logic chips, with a countdown, a counter and a state machine.
- logic ICs
- 47
- logic ICs
- countdown I built
- 10 → 0
- countdown I built
- attendance counter
- 0–29
- attendance counter
What it does
The system opens a timed attendance window, counts students as they check in, and shows the count on a two-digit seven-segment display, with green, orange and red LEDs showing the window's state.
A finite state machine drives it through idle, active, warning and closed states.
My part
We designed the system as schematic blocks in Quartus, then built it for real on breadboards from 47 74LS-series chips. I co-designed the hardware prototype and engineered the 10-to-0 countdown module from JK flip-flops.
The hardest part was making the physical board behave like the simulation. I debugged timing on the real circuit against the Quartus waveforms until the two matched.