Unlock a door or attendance log with RFID cards

Steps

1. Use a kit that already matches reader + MCU + display when learning.
2. Store authorized UIDs in EEPROM/Flash; avoid hardcoding only one card.
3. Drive door locks via transistor/relay — not MCU pins.
4. Add a manual override plan for lockouts.

Kits & catalog links

Start from project kits matching “RFID”, then fill gaps from parts.

Safety

• Electric strikes and solenoids need adequate current and freewheel diodes.

Assumptions

• Access control for real property may need local regulations and backup keys.