I have two Arduino's. One from .org, and one from .cc. The arduino.org one has really nice silk screening on the header pins. The arduino.cc one does not. In addition there are some visible component differences. One has a 504S (not sure what this chip is), one has a 504L. The button on the .org one is a bit more tactile. The headers on the top (not the ICSP) headers are missing on the .org one. And, the four points that look like they're for soldering or testing are absent. I can try to get a high-res picture of the two up.

I bought the .org one in a beginner kit online from Amazon (from the official seller). And, the .cc I bought from their website directly.

The .org one seems like it's made from higher-end components, and actually having the headers at the top makes it seem more polished. Is there any through guide to what these differences are or a changelog from one hardware revision to another?

  • 1
    This doesn't make a lot of sense - until fairly recently, arduino.cc's boards were supplied by the folks now calling themselves arduino.org and the pictures on arduino.cc all show very nice silk screen designation of the pin headers. What exact deficiency are you questioning? Are you sure these boards were obtained from the sources you think they were? Commented Jan 1, 2016 at 0:45
  • This is a new Arduino.cc board, presumably not made by the arduino.org folks. It lacks silk screens on the pins, actually lacks a whole set of of header pins, and has some different components. Some either minor imperfections too. The caps are crooked and don't line up like the Arduino.org one. Commented Jan 1, 2016 at 2:26
  • Is there any through guide to what these differences are or a changelog from one hardware revision to another? - I strongly doubt it.
    – Nick Gammon
    Commented Jan 11, 2016 at 9:34

1 Answer 1


No, there is nothing that documents the differences as in a changelog, purely because this is not an iterative change.

The two boards are designed and manufactured by two different (competing) companies in two different countries (USA and Italy) using different component suppliers.

Just because they both say Arduino UNO doesn't make them both the same board - not these days anyway, since the founders of Arduino got really childish and started throwing their faeces at each other like monkeys in the zoo.

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