9.4 Fixed-Point Data Types

The following table shows fixed-point data types that are supported by the compiler when the -menable-fixed command line option is specified. See Fixed-Point Arithmetic Support - dsPIC33C/E/F and dsPIC30 Only for more details on the compiler's support for the fixed-point C language dialect. If the signed or unsigned type specifier is not present, the type is assumed to be signed.

Table 9-4. Fixed Point Integer Data Types
Type	Bits	Min	Max
`_Fract`	16	-1.0	1.0 - 2^-15
`short _Fract`	16	-1.0	1.0 - 2^-15
`signed _Fract`	16	-1.0	1.0 - 2^-15
`signed short _Fract`	16	-1.0	1.0 - 2^-15
`unsigned _Fract`	16	0.0	1.0 - 2^-15
`unsigned short _Fract`	16	0.0	1.0 - 2^-15
`long _Fract`	32	-1.0	1.0 - 2^-31
`signed long _Fract`	32	-1.0	1.0 - 2^-31
`unsigned long _Fract`	32	0.0	1.0 - 2^-31
`_Accum`	40	-256.0	256.0 - 2^-31
`short _Accum`	40	-256.0	256.0 - 2^-31
`long _Accum`	40	-256.0	256.0 - 2^-31
`signed _Accum`	40	-256.0	256.0 - 2^-31
`signed short _Accum`	40	-256.0	256.0 - 2^-31
`signed long _Accum`	40	-256.0	256.0 - 2^-31
`unsigned _Accum`	40	0.0	256.0 - 2^-31
`unsigned short _Accum`	40	0.0	256.0 - 2^-31
`unsigned long _Accum`	40	0.0	256.0 - 2^-31

As with integer and floating point data types, all fixed-point values are represented in a little endian format, which means:

The Least Significant Byte (LSB) is stored at the lowest address
The Least Significant bit (LSb) is stored at the lowest-numbered bit position