Ethernet Board

Not really a problem.

Ethernet Board on UNO or vise versa.

Today I got a new Arduino UNO and Arduino Ethernet Board. Both original !
In my case the UNO fits on top of the Ethernet Board.

It doesn't mater for the funktion ( I think ).
I only wonder when I saw pictures on the Web > Ethernet Board is on top of the UNO ...

Anybody who know whats happen ?

That Arduino UNO ( is unusual. It has extended header pins (typically used only on shields). It also appears to have the ICSP header on the bottom. I have no idea why it was built like that.

That is an Arduino Ethernet (, not an Arduino Ethernet Shield ( It has the functionality of an Arduino UNO (except it has no USB-to-Serial section) and Arduino Ethernet Shield combined. It would be unusual to connect it to an Arduino UNO. You would typically use an FTDI Cable to program it.

"Ethernet Board on UNO or vise versa."
Neither. Don't use an Arduino as a shield on another Arduino.

If you had a normal Arduino UNO (with the ICSP header on top) and an Arduino Ethernet Shield then you should put the Arduino Ethernet Shield on top.

Thank you John !

I was knowing there was something wrong but not exactly what :o