It is as well possible to use the binary notation for constants instead of hexadecimal constants or normal constants. Note that binary constants are not allowed if the -Ansi: Strict ANSI compiler option is switched on. Binary constants start with the 0b prefix, followed by a sequence of zeros or ones.
#define myBinaryConst 0b01011 int i; void main(void) { i = myBinaryConst; }