Thread: Puzzling issue... Is typecasting the answer?

Check out sprintf().

No, for sure typecasting is not the answer. You can't use sprintf() without stdio.h, but you can convert each digit to it's ASCII value:

ASCII Table / Extended ASCII Codes

That will mean working thru the number with modulus.

Why not use the standard library? (At least the I/O parts should be there even in an embedded system, and that's where sprintf is.) (EDIT: I guess I was wrong -- stdio.h is not required in a freestanding implementation, although interestingly float.h is.)

If you do have to roll your own for whatever reason, you'll have to go back to how you learned numbers. Hint: 3120 is three thousand, one hundred and twenty.

I would like to know WTH floats have to do with converting an integer to a string. Is this some artificial constraint thought up by an instructor?

In any event one way to deal with this is to take your number as in integer and start up a loop that peels off a digit at a time. If you cannot use sprintf() and you cannot use itoa() (which is the correct answer) you can do something like:
1. Say your integer mainInteger is 1234;
2. Set up a char buffer of say 10 characters, memset it to zero.
2. while your integer is > 0:
3. int curDigit = mainInteger % 10; dividing mainInteger by 10 is 123 with 4 left over. The mod operator will stick the 4 into curDigit.
4. Add 48 (ascii code for '0') to curDigit and stick it into the first (right-hand) element of your char buffer.
5. mainInteger = mainInteger / 10;
6. goto 2

If you walk this logic on paper you will see one way of doing this. Hope this helps.

Well its either use the standard libraries or something by hand. I don't know what else you are going to do. Modulos are not 'ick' BTW and sometimes the only way to solve certain things...