Why is the default value of Flash FF instead of 00?

First, both FF and 00 are expressions in 16, FF is equivalent to 256 in 10, and 00 is equivalent to 0 in 10, which makes no sense. The default value of 0 is obviously inappropriate.

Second, if it is used as the background color value when the flash is turned on, FF stands for white, 00 stands for black, and white is generally used as the background, so it is F F.