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### baud rate parameter in rosserial_python arduino

Hi all,

I am trying serial communication between the Arduino and ROS using rosserial (http://wiki.ros.org/rosserial). It works perfectly with the default parameter for the baud rate:

rosrun rosserial_python serial_node.py _port:=/dev/ttyACM0


but when I give a different baud rate using this:

rosrun rosserial_python serial_node.py _port:=/dev/ttyACM0 _baud:=9600


I get the following error:

[INFO] [WallTime: 1428602466.003588] ROS Serial Python Node
[INFO] [WallTime: 1428602466.016732] Connecting to /dev/ttyACM0 at 9600 baud
[ERROR] [WallTime: 1428602483.124382] Unable to sync with device; possible link problem or link software version mismatch such as hydro rosserial_python with groovy Arduino


I have rosserial-indigo-devel installed and the ROS version is indigo. The above error comes only when you specify a baud rate other than 57600 (default baud rate).
I also looked into serial_node.py and changed the default baud rate to 9600 but then also, it only works with the baud rate of 57600 and gives error if some other baud rate is specified.

Does anyone know what can be the problem?