To begin making our own Arduino board, we r going to build a simple breadboard setup. It consists of two breadboards arranged as shown in the figure. Note the arrangement of two boards differs from ordinary setup. The board is divided into two parts viz. upper & lower.
|Two Breadboards arranged|
The Arduino circuit consists of a microcontroller and a USB-Serial converter IC ( FT232RL - to facilitate the microcontroller programming through USB port of your computer ).
You can use the ready made breakout board on the market for programing through USB port. Since we are going from scratch we'll be building our own USB-Serial Interface using that chip and I'll try to introduce the USB firmware( that can emulate the USB-Serial Interface without the FT232RL IC).
|Notice the difference.|
*Allocate space for different sections of the circuit separately.
*Reduce wiring complexity and use the wire of required length.
*Use a conventions of wire colors.
e.g: Red - SUPPLY
Black - GND
Blue - DATA
*Connect the lines of numbers 4 & 5 externally and use it as GND.