rosserial_python problem [closed]

edit

hi, i have an error when i run this command:

pi@raspberrypi ~/catkin_ws $ rosrun rosserial_python serial_node.py /dev/ttyACM0[INFO] [WallTime: 1462279527.419855] ROS Serial Python Node
[INFO] [WallTime: 1462279527.608365] Connecting to /dev/ttyACM0 at 57600 baud
Traceback (most recent call last):
  File "/home/pi/catkin_ws/src/rosserial/rosserial_python/nodes/serial_node.py", line 80, in <module>
    client = SerialClient(port_name, baud)
  File "/home/pi/catkin_ws/src/rosserial/rosserial_python/src/rosserial_python/SerialClient.py", line 382, in __init__
    self.requestTopics()
  File "/home/pi/catkin_ws/src/rosserial/rosserial_python/src/rosserial_python/SerialClient.py", line 389, in requestTopics
    self.port.flushInput()
  File "/usr/lib/python2.7/dist-packages/serial/serialposix.py", line 500, in flushInput
    termios.tcflush(self.fd, TERMIOS.TCIFLUSH)
termios.error: (5, 'Input/output error')

could you tell me what 's ths problem please? when i hsed just ultrasound sensor, all is ok but when i add also servo controller i receive this error. i use this configuration on CMake:

cmake_minimum_required(VERSION 2.8.3)

include_directories(${ROS_LIB_DIR})

# Remove this if using an Arduino without native USB (eg, other than Leonardo)
#add_definitions(-DUSB_CON)

generate_arduino_firmware(hello
  SRCS chatter.cpp ${ROS_LIB_DIR}/time.cpp
  BOARD uno
  PORT /dev/ttyACM0
)