5. CONFIGURATION
ATTENTION
Differently from other application tasks, when a depuration mark in the MainTask is reached,
the task of a Master MODBUS RTU instance and any other MODBUS task will stop running
at the moment that it tries to perform a writing in a memory area. It occurs in order to keep
the consistency of the memory areas data while a MainTask is not running.
5.5.5.2. MODBUS Master Protocol Configuration for Direct Representation (%Q)
To configure this protocol using direct representation (%Q), the following steps must be performed:
Configure the general parameters of the MODBUS protocol, such as: communication times and direct representation
variables (%Q) to receive diagnostics.
Add and configure devices by setting address, direct representation variables (%Q) to disable the relations, communica-
tion time-outs, etc.
Add and configure MODBUS relations, specifying the data type and MODBUS function, time-outs, direct representation
variables (%Q) to receive diagnostics of the relation and other to receive/write the data, amount of data to be transmitted
and relation polling.
The descriptions of each configuration are listed below in this section.
5.5.5.2.1. General Parameters of MODBUS Master Protocol - setting by Direct Representation (%Q)
The General parameters, found on the home screen of MODBUS protocol configuration (figure below), are defined as:
Figure 60: MODBUS RTU Master Setup Screen
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