Expression (expr), C.3.18 expression (expr) – Nematron Pointe Controller User Manual

Page 381

Pointe Controller User Guide

Appendix C: Ladder Diagram Block Reference

379

NOTE: This function does not check for bit register overflow. If overflow occurs,
the value “1.#INF00” (infinite) is placed in the output.

C.3.18 Expression (EXPR)

As it is currently implemented, the EXPR block simply assigns the value of the
input to the output. In future releases this function will allow expressions to be
defined and executed as part of the diagram.

Select the

tool (from the

Math Blocks

toolbar) and click on a ladder rung to

insert the following block:

Once the block is inserted, you can double-click on it to

configure

it.

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: the Input Value (IN) is
directly assigned (copied) to the Output Value (OUT).

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

Enable

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

ENO

Enable
Out

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