I'm getting some blank 1284's in the mail today, and I just want to confirm that I'll be able to use them with Arduino Code/IDE just like a 328? I'll plan to use Nick Gammon's bootloader (which it seems works with the 1284), and then I should be able to upload code using an empty (chip removed) UNO and connecting TX, RX, VIN, GND, and Reset, right?
Anyone have any other advice or insights into using a 1284?
Thanks!
You will need to install the core (can be done manually our using board manager, see the Arduino on other avr chips page for the url. On phone, so I can't easily get a link in here)
You can also use a usb serial adapter instead of a chip-less uno. Just make sure it brings out the dtr pin. They're a few bucks each on eBay, and way smaller than a while uno board...
You need to modify your IDE. I would recommend a separate FTDI USB adapter and caps + crystal. There are several issues using 1284P but a few of us, CrossRoads, Jack Christensen, myself, and some other, have experience with it.
Jack's 1284p mod for Arduino IDE