We talk again of Serialino, our Arduino's clone: this time the printed circuit board (PCB) design is shown.
Here beside you find a screen-shot of the PCB of Serialino, numbered 1.0.
Even from here you should be able to distinguish the areas described in the previous post.
Power supply section on the bottom-left; the communication port and IC Max232 on the top-left; the headers on top and bottom; and finally ATMega with external oscillator, then the switch button and the ICSP pin headers.
Last time we talked about the importance of prototyping, when you decide to develop an idea involving electronics; this is worth especially if everything is direct to get the final result into a copper board.
The better the prototyping, the more efficient the copper board.
You know that the signal's integrity on breadboard is affected but multiple sources of noise: the capacitances and resistances due to the internal paths are just a little example, being negligible for standard circuits in DC or low frequencies power supplying.