Definitions, Eqp logic editor – Det-Tronics S3 Graphics User Manual
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EQP LOGIC EDITOR
Version 6.0
EQP LOGIC EDITOR
Definitions
Programs
Programs are the highest-level executable elements within an S
3
project. Programs can invoke functions or
function blocks, but cannot invoke other programs. Projects are typically partitioned into multiple programs
based on the operational requirements of an installation.
Function Blocks
In S
3
a function block is an executable element that yields one or more values and is
generally used to perform repetitive operations. Variables within a function block persist
from one evaluation of the function block to the next, so that the values calculated for
one evaluation can be used in the next. Therefore, invocation of the same function
block with the same input values may not yield the same output values. Examples of
such function blocks are timers and counters like the Timer OFF delay (TOF).
Functions
A function is an executable element that yields exactly one result. Unlike function blocks,
variables in a function do not persist from one evaluation to the next. An example of a
typical function is the boolean “AND” gate. Two or more inputs are evaluated and result
in a single output.
Extensible Functions
These functions have a minimum of two (2) inputs and can have a maximum of thirty two (32). The number of
inputs into the function can be adjusted by double clicking on it.
This will open a dialog box allowing the input number to be set and also may allow inverting any or all of the
inputs as well as the output.
In the AND gate example to the right, the default
of two non inverted inputs and a non inverted
output are shown. To change the extensible
number of inputs, click on the arrow to the right
of the “Number of Inputs” field.
LOGIC CREATION • DEFINITIONS