Atmega 328P-AU


I want to programm a naked 328P-AU and I made a test board
based on some informations (Nick Gammon) I found on the net.

Question: Will this board work (C3)?
Do Im missing something?

Thank You,

-What's R2 for? (just curious) -What's D1 for? (just curious) -I've seen Aref unconnected on most cases. -I'd recommend a resonator, so you won't have to deal with C1 and C2, unless you need a higher precision clock.

R2 limits current out of Tx pin in case of shorts. D1 prevents any spikes on reset pin from starting the High Voltage (12V) programming sequence and making the chip act like it is hung up. Aref good as is. C1/C2/xtal will allow for better high speed comm's.

I would ditch R6, use the internal pullup, and close the switch to Gnd - look for a low on D6 instead of a high.

It's not that common to see a minimal at328 test board using a TQFP package, they are the 28 pin DIP package 99% of the time. So long as you meant to use the 32 pin flat pack, you should be okay... But if you plan to use the DIP part, all your pin assignments are incorrect.

@All Thank You very much.

I thought using TQFP package will be more challenging.

@CrossRoads: I was not sure about that R6 switch. I’ll modify my setup.
I don’t understand why the most people using external resistor with switches on port C and port D.

Thank You again,
I’ll come back with my results.

Why? Because they don't know any better.