Nematron Pointe Controller User Manual

Page 397

Advertising
background image

Pointe Controller User Guide

Appendix C: Ladder Diagram Block Reference

395

Functional Description

This block always passes the Enable input state (EN) through to the Enable Out
output state (ENO) without change; when EN becomes on, ENO is turned on, and
when EN becomes off, ENO is turned off.

When EN becomes on, the block function is executed: a bit-for-bit logical
inversion is made upon the Input Values (IN) and the result is placed in the
Output Value (OUT).

Each bit in IN is evaluated according to the following table:

IN

0

1

OUT

1

0

Therefore, a 16-bit example of NOT would be:

IN1: 1010010101011101

OUT: 0101101010100010

The block function is executed every time the ladder is

scanned

, so long as EN

remains on. If EN becomes off, then OUT remains at its last calculated value until
EN becomes on and the block function is executed again.

Configuration Reference

The parameters of this block are described in the following table:

Param

Name

Config

Var Type

Description

EN

Enable

no

-

The state of the rung (off/on)
received from the left.

ENO

Enable
Out

no

-

The state of the rung (off/on)
passed to the right.

IN

Input
Value

req

any integer*

T_DONE

T_VALUE

T_PREVAL

The input value.

OUT

Output
Value

req

any integer*

The result of a bit-for-bit NOT
inversion upon the input value.

* Any Input, Output, or Memory tag except 32-bit Real (F). For more information, see “

Defining Input,

Output, Memory tags

” on page 114

.

NOTE: If the function result is larger than the output variable (for example, a 16-
bit result to be placed in an 8-bit output variable), then the high-order bits of the
result are discarded and the low-order bits are placed in the output.

Also, this function does not negate or invert the sign of a signed variable. To
invert the sign of a signed variable, configure an

XOR function

with the variable

to be inverted as the first input value and –1 as the second input variable.

Advertising