Quick query (I hope).
I have an Arduio R3 board with ATMega328P U on board. It works fine. I bought some new MCUs, ordered with bootloader. Same IC designation. Before I dive into my new project I want to confirm they are okay.
So ...............I take the original MCU out of the Arduino R3 and replace it with a new ATMega328P U. Should it work fine straight away? i.e. can I upload simple sketches like Blink?
My problem is that I've done this and none of them work. I get two flashes on the Rx LED on the board, then ArvDude gives me a string of "not in sync" error messages. If I put the original MCU back in then everything works okay again. I don't want to go through the hassle of burning bootloader on chips that supposedly have it, I'd rather send them back.
Are my new MCUs duff? Or is there any other easy way to check them?