stdint.h and stdbool.h for Keil C51

Interestingly, Keil C51 does not ship with C99 compliant stdint.h and stdbool.h header files.

But there is no need to dispair. The stdint.h from SDCC seems to work ok however I personally would not trust the pointer types and widths. However in a context of a 8051 MCU, I’d rather introduce my own data type for pointers anyway due to the different possible memory spaces. A generic pointer will have to carry section information that has to be evaluated at runtime. A special typed pointer won’t waste as many resources.

The stdbool.h from SDCC can be used as well. Just make sure to be Keil compatible and use the following definitions:

#define _Bool bit
#define BOOL bit
#define bool _Bool
#define __bool_true_false_are_defined 1