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C COMPILER->C Language Definition->Data Sizes

The data sizes for the Crossware 8051 C compiler are given in the following table.  Signed is the default type but may be explicitly declared for all data sizes using the signed keyword.

(1 byte is 8 bits)
    

Type	Storage Size

Char	1 byte
short int	2 bytes
long int	4 bytes
int	2 bytes
unsigned char	1 byte
unsigned short int	2 bytes
unsigned long int	4 bytes
unsigned int	2 bytes
float	4 bytes
double	8 bytes
long double	8 bytes
enum	Up to 4 bytes
bit fields	Up to 32 bits
bit	1 bit

Integers are stored least significant byte first.
Floating point types are stored internally in IEEE 754 format, lease significant byte first.

Note for users upgrading from the 8051PSDS:  The 8051PSDS-A stores variables in the reverse order to the 8051PSDS.