RX / TX always on

I bought a batch of assembled usb boards

They seem to be working fine but when I power them from the power in, the RX / TX lights are always on. If I power by USB, they go off.

Any idea why???


It's normal, albeit a bit strange. I'm not sure of the details, but basically since the FTDI USB chip isn't powered, the LED logic isn't connected and the LEDs flicker/turn on.

you can consider it a “bug” in the current arduino board v3 which has been fixed in version v4
which will be called Arduino NG and will be available from the day Ars Electronica opens.