[werk_ag]

I did some research on google about Arduino USB communication freezes. There are lots of info about it. Most of the times the problem is on the PC side:

- Some USB 3 ports or hubs are problematic.
- Some serial to USB 64 bit drivers are problematic.
- Noise cables

How some people have solved similar freeze problems:

- Change the Arduino to another PC usb port, not on the same hub
- Change the Arduino to one with a FTDI chipset.
- Run the Arduino in a 32 bits system.
- Use USB cables as shorts as possible (One inch is short. 18 inches is an antenna.)

Hope this hints help.

Seems a joke, but it isn't.

I was testing serial communication with the simple code from zoomkat, and I found what was causing this: the refrigerator... that's right, the refrigerator...

This might seem like a bad joke, but I replicated this 4 times today and I didn't believe it either. Every single time the refrigerator turns off, the serial connection just breaks.

The only connections is that the computer and the refrigerator is plugged in the same wall socket.
Being an old fridge, I'm guessing an electric impulse is sent through the wall socket, through the power supply, and somehow messes up the USB port.

Source: http://forum.arduino.cc/index.php?topic=...#msg754337