Rievtech ELC Series - Page 231

EN
Programmable Relay ● User Manual for ELC, EXM and PR Series 231 2020 v6.0 ● © Rievtech Co.,
Ltd. ● www.rievtech.com
This function provides for storing 16-bits of data, two
characters using the Decimal value of each character,
which can be used in MQTT communications.
A maximum of 512 VW blocks can be used per xLogic PLC
program and the number is reduced with every occurrence
of VB or VD blocks used.
This block can be used by the Subscribe MQTT function
to determine the start character position of a string to be
received.
Connection
Description
Input En ( )
A high signal at En input will enable
this function block to be activated
Output Q
Q is set (1) or reset (0) depending
on whether the block is active or
not.
Input En ( )
A high signal at En input will enable
“Modbus Read” function block to be
activated
Example:
Figure 56 - Storing VW Data
Any characters received by the above block will be stored
starting in block VW0. The maximum number of characters
allowed is 256. You can also specify a Start value, which
could be used as a start of message indicator.
NOTICE:
VW Blocks would show the AF1 value with high
and low bytes swapped. VW1 will start with the same
value as the end of the previous VW block as shown
below. VW use Modbus addresses 0x6800 to 0x7000.
Figure 57 - VW Block Memory Usage