Rockwell Automation 1398-PDM-xxx IQ Master Version 3.2.4 for IA-2000 and IQ-5000 Positioning Drive Modules, IQ-55 User Manual

Page 233

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Language Reference • Reference

211

Publication 1398-PM601A-EN-P — October 2000

WORDS

Gn

Variable, Nonvolatile, User

Variable

Purpose

Load a user-defined variable with a value from another variable, result of a math
expression, a constant, a timer, or an analog input.

Syntax

Gn = value
variable =
Gn

n

The number of the variable. n = 1, 2, 3, ..., 64.

value

Value can be a constant, a nonvolatile variable Gn, a volatile
variable Vn, or a system variable.

variable

The variable may be a nonvolatile variable Gn, a volatile vari-
able Vn, or a system variable

Remarks

G and V variables are stored internally as 4 bytes for the mantissa (the part before the
decimal point), 2 bytes for a numerator (the top part of a fraction), and 2 bytes for a
denominator (the bottom part of a fraction). The range of numbers that can be repre-
sented in 4 bytes is

±

2,147,483,648. The range of numbers that can be represented in 2

bytes is

±

32,767. Therefore, the range of numbers that can be contained in a G or V

variable and any intermediate value is:

The changes made to Gn remain in effect even after power is removed. Changes made
to a Gn by one program will be seen by other programs. Vn variables are volatile and
will lose their values when power is removed

TIP: Variables can be assigned names using the ASSIGN command and then refer-
enced by those names to make the program easier to read.

See Also

Vn, Fn, Bn, Part 4

Programming, Arithmetic

Example

G7 = ADC1

G14 = PCMD

G7 = V7 + 1

G8 = TIMER1

G9 = POS1

G or V =

±

+ ±

±

2 147 483 648

32 767

32 767

,

,

,

,

,

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