Suggestion on Serial Communication Robot Driving

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Hi there !

I have the custom made differential drive Robot Base which connect through USB ( /dev/ttyACM0 )

and i want to control it via joystick teleop.

THE PROBLEM IS

1. the robot base , which have no driver at all. i need to write the special driver for it. (please look below for the protocol) any example or suggestion ?
2. How to send message from the ROS to serial ?( maybe the cmd_vel is the good msg to send )

Serial Protocol Example

to drive Robot forward = Serial Send byte Stream in this format

255 255 001 007 003 020 001 255 001 255 224

Stream Explained

255 255 001 - Header

007 - Length of byte following this byte

003 020 - error on the protocol (it doesn't matter in this context)

001 - Direction of Right Wheel

255 - Velocity on Right Wheel (Full Throttle)

001 - Direction of Left Wheel

255 - Velocity on Left Wheel (Full Throttle)

224 - Inverted Checksum

Things that i've done :

I can use the joystick teleop to control turtlebot_sim.

For the base : i can completely drive ,control and read value manually on ordinary C++ code ( respect to the WJWWOOD Serial Library ).

So, I want to know that there're any node example, suggestions or tutorials to achieve this ?

Many Thanks, Tew