Don't talk to the serial port after close (fix #910)
Don't talk to the serial port after close (fix #910)

ManiacalLabs/BiblioPixel,ManiacalLabs/BiblioPixel,rec/BiblioPixel,ManiacalLabs/BiblioPixel,rec/BiblioPixel,ManiacalLabs/BiblioPixel,rec/BiblioPixel,rec/BiblioPixel