By the way, I did manage to get the LCD to work by 
polling the busy flag.  In class you said a TA had trouble doing this.<br><br>

I think I might know what went wrong.  
If you poll the busy flag, you still need to insert a delay after it 
before polling it again.  Otherwise you get stuck in an infinite loop.  
I was having trouble with this at first.  That's why I bring it up as 
a possible source of error from the TA.  However, I don't know how 
much more efficient checking the busy flag is in comparison to 
inserting a delay after every character (since the busy flag requires 
its own delay).  However, it does save some typing time since you don't 
have to actually JSR to a delay routine after writing each individual 
nibble.