Vector VEC-VA Series User Manual

VA Motion Controller Programming Manual
175
1 0.2 function block
A function block is a program organization unit POU with multiple input and output
parameters , which have internal memory, and the return value of the function block depends on
the value of its internal storage unit. The abbreviation of the function block is FBD different from
the previous function. The function block must be instantiated. The instance name can be the
default name or the default name. The instance name must be unique within
the POU . In FBDAnd LD programming, this instance name appears in the upper part of the function
block.
The following function blocks can be used during MULTIPROG programming
○ bistable function block
○ Pulse edge detection function block
○ counter function block
○ timer function block
Command functions included in the block ( in the editor wizard from the drop-down
list " function block ")
name
description
CTD
Down counter
CTU
Increment counter
CTUD
Up / down counter
F_TRIG
Falling edge detection
R_TRIG
Rising edge detection
RS
Reset priority
SR
Set priority
TOF
Disconnect delay timer
TON
On-delay timer
T P
pulse
10.2.1 CTD (Decrement Counter Instruction )
IL programming language
LD, FBD programming language
Function: The TD instruction is used to count down the input. When the LOAD terminal
is FALSE , if there is a rising edge at the CD input, the CV terminal is decremented by 1 . If the
count value CV reaches the lower limit value 0 of the counter , a TRUE signal is issueDAt
the Q output , and the CTD function block stops counting. When the LOAD terminal is TRUE , the
counter stops counting anDAssigns the value of the PV input to the CV terminal.

Vector VEC-VA Series Specifications

General

Brand	Vector
Model	VEC-VA Series
Category	Controller
Language	English