Invalid conversion from int to const char is what it says, and highlights that line. I agree that an integer is what | am looking to extract. The error code I quoted, I suppose, creates some confusion.
Here are the error lines on the compiler:
RoverIpad.ino: In function 'void joystickJoystickMoveRightCallback(int)':
RoverIpad:207: error: invalid conversion from 'int' to 'const char*'
RoverIpad:207: error: initializing argument 1 of 'int atoi(const char*)'
What I am trying to do is extract the value and convert it into a 90-180 integer. Not sure what I've done wrong, as similar code works elsewhere.