Canon F-300P

The Canon F-300P is unusual in more ways than one. This machine is both highly useful and quite frustrating at the same time. Useful because it has a multitude of functions, a large display, a clean and logical layout. Frustrating because - you guessed it - the darn thing has no program flow control! Although it has plenty of room in its program memory, all you can enter is plain formulas, nothing more. Well, a little bit more: apparently, one memory register can be used to implement a simple loop. But even this feature is not really meant for program control, but more to permit the operator to perform the same calculation interactively multiple times.