Ever felt you wanted a new Arduino for a project that you have been planning to do for a while, but reluctant to buy a new one or pull out an old one from another project ?
In this tutorial I will show you how to build a minimalist Arduino on a breadboard !
Here are the parts you will need :-
- Bootloaded AVR Atmega 328 microcontroller
- Crystal Oscillator (16Mhz)
- push button switch
- Resistors (10k, 330 ohms)
- two ceramic capacitors (22pF)
- USB to TTL converter
- connecting wires
So, let’s get started !
1) First of all, slot the micro controller and the push button switch onto the breadboard as shown below. Connect up the power and ground rails on either sides of the breadboard.
Note:- You can buy an Atmega 328 micro controller that has already been bootloaded or you can bootload it yourself using another Arduino. http://arduino.cc/en/Tutorial/ArduinoToBreadboard or, you could choose to use an AVR ISP to bootload the chip.
2) Build the clock circuit consisting of the crystal(16Mhz) and capacitors(22pF). The two leads of the crystal are connected to pins 9 and 10 of the micro controller. Add the pull up resistor(10k) to pin 1 of the micro controller. Also connect one end of the switch to pin 1 and the other end to ground. This acts as the Reset switch.
3) Next, connect pins 7, 20, 21 to VCC and 8, 22 to Ground.
4) Finally, connect the TTL converter to the micro controller and also add an led to digital pin 13 (pin 19 on the avr microcontroller) as shown below.
A TTL converter looks something like this :-
5) Install the drivers for the TTL converter, then try uploading the Blinky sketch. You would have to click the Reset button every time you upload any code to the chip. Some TTL converters come with a auto reset pin. You could get one of those if you like.
That’s it !
Happy hacking ! 🙂