C translator for calculator project

[Druzyek]

A good place to start might be the shunting yard algorithm or something similar. You can convert algebraic notation to a stack based format that matches what your calculator uses internally. Out of curiosity, why C? I think a lot of calculators use a BASIC-like language so you don't have to worry about types and usually don't need pointers. It's probably not the case that you would write a lot of lower level code in the on board language, right?