TheEpicSnowWolf:
True, but for my case, it actually does.
How to convert char to integer - #2 by septillion - Programming Questions - Arduino Forum
That's a different type of expression.
test[0] - '0'
the above gives the numeric value of the character contained in test[0].
0 -'0'
does not convert anything, but is just a constant (0xD0 in a byte/char context).