User`s manual

Dynamic C User’s Manual digi.com 25

4.3 Data

Data (variables and constants) have type, size, structure, and storage class. Basic (a.k.a., primitive) data

types are shown below.

4.3.1 Data Type Limits

The following symbolic names for the hardcoded limits of the data types are defined in limits.h.

Table 4-3. Dynamic C Basic Data Types

Data Type Description

char 8-bit unsigned integer. Range: 0 to 255 (0xFF)

int 16-bit signed integer. Range: -32,768 to +32,767

unsigned int 16-bit unsigned integer. Range: 0 to +65,535

long 32-bit signed integer. Range: -2,147,483,648 to +2,147,483,647

unsigned long

32-bit unsigned integer. Range 0 to 2

- 1

float

32-bit IEEE floating-point value. The sign bit is 1 for negative

values. The exponent has 8 bits, giving exponents from -127 to

+128. The mantissa has 24 bits. Only the 23 least significant bits

are stored; the high bit is 1 implicitly. (Rabbit controllers do not

have floating-point hardware.) Range: 1.18 x 10

-38

to 3.40 x 10

enum

Defines a list of named integer constants. The integer constants are

signed and in the range: -32,768 to +32,767.

#define CHAR_BIT 8

#define UCHAR_MAX 255

#define CHAR_MIN 0

#define CHAR_MAX 255

#define MB_LEN_MAX 1

#define SHRT_MIN -32768

#define SHRT_MAX 32767

#define USHRT_MAX 65535

#define INT_MIN -32767

#define INT_MAX 32767

#define UINT_MAX 65535

#define LONG_MIN -2147483647

#define LONG_MAX 2147483647

#define ULONG_MAX 4294967295