Build your own Speedometer!

**Disclaimer**
This is not a legit tutorial, but just a preview.

Recept of Speedometer

Introduction:

In my class of Embedded System, I decided to build a wireless speedometer for my bike since I didn't buy it for my bike.

Ingredient:

Atmel Atmega32 * 1
40 DIP socket * 1
8Mhz Crystal * 1
HC05 Bluetooth module * 1
Reed Switch * 1
Magnet * 1
9V Battery * 1
LM7805 * 1 (equivalent 5v regulator)
Perfboard * 1
Pin sockets * 1 bunch
Solder wires  * 1 bunch
Single-core wires * 1 bunch

Instruction:

1. Plan out your circuit diagram!!! Make sure you get the right side of the chip and other components (because I made a stupid mistake which made me re-solder everything).

2. Check you circuit diagram again and again. This can save your components second or third lives.

3. Put your components on the perfboard, but not solder yet. You may use some solder wire to hold the temporary position.

4. Hold your breath and solder them!

5. After soldering, check if the circuits are matched with your diagram.

6. Put the components on and ...... boom!

Result:

Besides the hardware, I have also built an Android app for the user interface:

For more information or code, you may have a look of there: https://github.com/peteroid/avr-study-projects (in the folder of bike-speedometer)

Stay tuned for the next awesome project!