GE 90-30/20/Micro manual Data Types, Type Name Description Data Format, Byte, Real

2

Data Types

Data types include the following:

Table 2-5. Data Types

Type

Name

Description

Data Format

INT

Signed

Signed integers use 16-bit memory

Register 1

Integer

data locations, and are represented

in 2’s complement notation. The

S

(16 bit positions)

valid range of an INT data type is –32,768

16

1

to +32,767.

DINT

Double

Double precision signed integers are

Precision

stored in 32-bit data memory

Register 2

Register 1

Signed

locations (actually two consecutive 16-bit

S

Integer

memory locations) and represented in 2’s

32

17

16

1

complement notation. (Bit 32 is the sign

bit.) The valid range of a DINT data type

(Two’s Complement Value)

is –2,147,483,648 to +2,147,483,867.

BIT

Bit

A Bit data type is the smallest unit of

memory. It has two states, 1 or 0. A BIT

string may have length N.

BYTE

Byte

A Byte data type has an 8-bit value.

The valid range is 0 to 255 (0 to FF in

hexadecimal).

WORD

A Word data type uses 16 consecutive

bits of data memory; but, instead of the

bits in the data location

representing a number, the bits are

Register 1

independent of each other. Each bit

(16 bit positions)

represents its own binary state (1 or

16

1

0), and the bits are not looked at

together to represent an integer

number. The valid range of word

values is 0 to FFFF.

BCD-4

Four-Digit

Four-digit BCD numbers use 16-bit data

Binary

memory locations. Each BCD

Register 1

Coded

digit uses four bits and can represent

4 3 2 1

(4 BCD digits)

Decimal

numbers between 0 and 9. This BCD

16

13

9

5

1

coding of the 16 bits has a legal value

range of 0 to 9999.

REAL

Floating

Real numbers use 32 consecutive bits

Point

(actually two consecutive 16-bit memory

Register 2

Register 1

locations). The range of numbers that can

S

be stored in this format is from ±

32

17

16

1

1.401298E-45 to ± 3.402823E+38.

(Two’s Complement Value)

S = Sign bit (0 = positive, 1 = negative).

GFK-0467K Chapter 2 System Operation 2-23