stty -F /dev/ttyUSB0 9600
echo "c2\r\n" > /dev/ttyUSB0
sleep 20
echo "a2\r\n" > /dev/ttyUSB0
sleep 20
echo "b2\r\n" > /dev/ttyUSB0
sleep 20
echo "a2\r\n" > /dev/ttyUSB0
sleep 20
echo "z0\r\n" > /dev/ttyUSB0