Thread: Big Letter became small letter

I writted the following code:

Code:

#include <stdio.h>

main()

{

        char ch, newch;

        printf("Add a character: ");
        scanf("%c", &ch);
        newch =  223 & ch;
        printf("Big letter: %c\n", newch);

}

so when i run it i write a small letter for example:

Add a character: a
Big letter: A

now, i try create a program that will get a big letter and make it small but i don't have no idea how to do this in ASCII I tried using
newch= ch & 223; but still the same?
any ideas could be useful, thanks!