I've looked around a ton so it's probably not available but does anyone know if there is a usable core for the ATMega16u2 (the chip the Uno and Due uses for USB to Serial). I have a project I was going to use the 32u4 for but they aren't really available for several months and the 16u2 has all the functionality that I would really need.

  • "171 in stock" Jun 29, 2014 at 15:24
  • I need the actual IC, NOT a board that already has it.
    – Adam Haile
    Jun 29, 2014 at 15:25
  • :O I... I don't think I've ever seen so many 0s before... Newark has a few -MUs, but I think someone bought up the world's supply of -AUs. Jun 29, 2014 at 15:40
  • Yup :( Was very dissapointed that basically no one has them...
    – Adam Haile
    Jun 29, 2014 at 15:40
  • 3
    A thought just occurred to me. If a 16U2 will do, then why not use a 16U4 instead? All you'd need to change is the amount of flash available. And DigiKey has a few hundred of those in stock in -AU. Jun 30, 2014 at 4:08

1 Answer 1


As @IgnacioVazquez-Abrams said, a 16u4 is virtually identical with a 32u4, so you can use a Leonardo or Micro core with a tiny modification to boards.txt. A 16u2 is a rather different animal, with fewer timers, many fewer pins, and no A/D converter, so you’d have to do a fair amount of editing to obtain a usable Arduino core.

That said, if you’re reasonably fluent in C++, building your own Arduino core is not very difficult, and I found it an instructive exercise. If you care about getting your project up as quickly as possible and not get sidetracked, however, go with the 16u4.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.