Electronic Code Lock

This a simple electronic lock which allows you to tinker with 555 timers CD4017, chips and combine slighty more challenging circuits with simple code. The lock works by using the counting feature and the reset and control feature of the 555 timer to only allow selects high voltages from certain pins, Because of this by, wiring the pushbuttons, to the pins that stay high when the rest stay low, it will turn on. Making a makeshift code lock without any microcontrollers required. Then the reset feature of the 555 timer will connect to a led and the circuit allowing you to reset the lock the circuit again. The password chosen for this code lock is 4529,

Components and Costs:

Raspberry Pi 3 or newer with extension board: $75.00

1 Photoresistor: $1.50

11 Pushbuttons: $0.50 each = $5.50

2 x 555 Timer ICs: $1.00 each = $2.00

4 Diodes (e.g., 1N4007): $0.20 each = $0.80

Resistors:

1 x 1kΩ: $0.10

-2 x 100kΩ: $0.20 each = $0.40

-1 x 560Ω: $0.10

-1 x 470Ω: $0.10

-Total for Resistors: $0.70

1 CD4017 IC: $1.50

1 Breadboard: $10.00

3 Different Color Wires: $3.00

1 x 9V Battery: $2.50

2 Standard Perfboards: $2.00 each = $4.00

Optional Male-Male Jumper Wires (set): $5.00

Soldering Materials and Costs:

Soldering Iron: $20.00

Solder Wire (Lead-free, 50g): $10.00

Soldering Flux (Paste or Pen): $5.00

Soldering Iron Stand with Sponge: $8.00

Desoldering Pump (optional): $5.00

Total Cost:

1. Electronics: $111.50
2. Soldering Materials: $48.00
3. Grand Total: $159.50 CAD

Watch a video on how the 555 timer and CD4017 work so you can understand the logic that is happening during the various proccesses in the circuit.

First create the project on a breadboard in order to practice and make sure all the components are in order and working correctly. Follow the schematic properly and make sure your not missing any wires or connections.

Set up your rasberry pi by using your sd card reader and watch the video in order to install rasbian or noobs. So that you can implement the code into your breadboard circuit. After finishing the code add the appropriate Gpio pin to the powerline of the Led connected to the Lock.

This is a optional step that makes the circuit function much better because all the components are internally wired together meaning less loose connections and less margins of error. Doing will make a much better and neater project but not doing it would mean it would still work on the breadboard. While allowing you to save time,money and of course it's easier.

Change the code and circuit according to your liking and design a project you can be proud of . Make sure you have a lot of fun while making the assignment.