Quote Originally Posted by Thinh Cao View Post
Thank you so much for your help !!!
You're welcome.

Quote Originally Posted by Thinh Cao View Post
btw if I changed the constant to a char, say I do:
#define RED 'X'
this is still correct and on the board, when I assigned an index to RED, it will appear on the screen at X right ?
Yes, it is correct and works as you expect.

Nitpick: the constant 'X' appears to be a char but is, in fact, an int (that's one of the differences between C and C++).
You can continue to think of constants in the form 'X' as chars.