Arduino Uno Setup
If you already have an Uno, or will use JMRI to control your trains, then by all means use an Uno. Just remember that you can’t have WiFi, Ethernet or a few other options due to memory limitations. But as a Command Station connected to JMRI with a USB cable it works great.
Setting up the UNO is essentially the same as setting up a Mega, so refer to the Initial Assembly page for information on setting up this microcontroller.
Uno R4 is not supported
If you choose to purchase an Arduino Uno, it is vital that you purchase the Revision 3 (R3) version, not the Revision 4 (R4) version. The EX‑CommandStation cannot run on the R4 version. See here from more information.