next topic »

[on:]

I recently bought an USB to Serial adapter so i can send my sketches to atmega328, and has DTR pin available... so i dont need to manually reset the atmega chip


this is the pin layout


what i would like to know is:
if i have a breadboard arduino that is receiving power via external source that goes through the 7085 voltage regulator ... like this:


in order to use the adapter to send sketches to atmega328 do i still have to connect the +5v of the adapter to atmega's VCC ?! Or that would be only if i wanted to power the arduino via USB ?

Thanks

[Reply #1 on:]

Connect CP2102 Vcc in place of 7805 output if you want to power the arduino via USB.
Make sure to connect ground up no matter what.

[Reply #2 on:]

Thank you very much

[Reply #3 on:]

Actually i have one more question...
how could i implement a switch (manually or automatic ) so i could chose whether to use power from usb or external battery?

[Reply #4 on:]

Get a singlepole, double throw switch.
Connec the 2 power sources to the NC and NO contacts, and the Common to the 5V rail.