All started with having blank ATMega328P-PU. The idea was to use it with CP2102 USB UART module to build The Shrimp but having seen also Arduino on breadboard I decide to combining the two and the result is:
When uploading applications using the USB UART, connect the +Vcc to USB UART (yellow jumpwire on 28th position) and disconnect the power supply
When running the uploaded application, unplug the yellow jump wire on 28th position and plug the power (of course if you wish you can use the USB as power, then just do not disconnect it):
In this case, the uploaded application is Arduino’s example Blink. It blinks the LED connected to Arduino’s pin 13 which corresponds to pin 19 on ATMega328P.