Anyone know of a tutorial on converting data types? That apply to Arduino.

I am in need a definitive tutorial on converting between data types in Arduino. The function I am calling only takes const char but the data is ints, unsigned ints, strings and float.

The Arduino is programmed in standard C and C++, so look for tutorials for those languages. I sometimes find this collection to be useful: http://www.tutorialspoint.com/c_standard_library/

John3gig: The function I am calling only takes const char but the data is ints, unsigned ints, strings and float.

Can you please provide an example program showing what you need to do. For instance, is the function in a library or did you write it yourself ?

You appear to have have decided that the way to solve the problem is to convert the data into an const char but that may not be the best approach or it may be impossible. In which case the problem may need to be tackled in a different way.