905 Padlock
905 : Padlock
- Author: J. Rosenthal & htfab
- Description: Set a code for your precious safe
- GitHub repository
- Open in 3D viewer
- View in Wokwi
- Clock: 0 Hz
- Feedback: 🟡 1
How it works
Set a code for your precious safe! Controls
- Pin 1 is used to reset the safe.
- Pin 7 is used to set your code (ON = set, OFF = locked)
- Pins 2 to 4 are used to set the code.
- The clock button is used to enter your code.
How to test
Set the clock to manual mode. Set your desired code using pins 2 to 4. Once you've done so, toggle pin 7 to ON, press the clock button then toggle pin 7 back OFF--the safe is now set! Turn ON pin 1, and press the clock button. The seven segment display should show "L" (for locked). Next turn OFF pin 1 to begin entering codes.
External hardware
None
IO
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | segment a | ||
| 1 | reset | segment b | |
| 2 | code bit 0 | segment c | |
| 3 | code bit 1 | segment d | |
| 4 | code bit 2 | segment e | |
| 5 | segment f | ||
| 6 | segment g | ||
| 7 | set code |
User feedback
- htfab👑: There are some errors in the circuit causing the saved code to invert on every clock cycle and the third bit of the code to be ignored. You can unlock the padlock by trying the correct code twice in succession, but some invalid codes are also accepted.