After upgrading to Mac OS X 10.11.1, the PL2303 USB-serial driver didn’t work any more.
I used minicom for console connection. In my old configuration my device was /dev/tty.usbserial. After installing the driver from www.mac-usb-serial.com the changed to /dev/cu.Repleo-PL2303-00001014.
Find this with:
$ ls /dev/cu.* /dev/cu.Bluetooth-Incoming-Port /dev/cu.Repleo-PL2303-00001014
Starting minicom -s you can easily follow the menu and change this.