Re: Fixed point DSP
Only one concept: you can work as with integers but you need to assign certain bit as integer boundary (fixed point) and be careful that in all your operations the operands must be normalized (with the fixed point in the same position) taking special care of point shifts because of multip./divisions. It's a burden for you but not a difficult task. The main challenge it's to select what bit of your many times 16 bit processor must be "the point" for best fit of your application (range vs leakage).
Cheers ;-)