5. CONFIGURATION
ATTENTION
Differently from other application tasks, when a depuration mark in the MainTask is reached,
the task of a MODBUS RTU Slave 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.
5.5.6.2. MODBUS Slave Protocol Configuration via Direct Representation (%Q)
To configure this protocol using Direct Representation (%Q), you must perform the following steps:
Configure the general parameters of MODBUS slave protocol, such as: communication times, address and direct repre-
sentation variables (%Q) to receive diagnostics and control relations.
Add and configure MODBUS relations, specifying the MODBUS data type, direct representation variables (%Q) to
receive/write the data and amount of data to communicate.
The descriptions of each setting are listed below, in this section.
5.5.6.2.1. General Parameters of MODBUS Slave Protocol – Configuration via Direct Representation (%Q)
The general parameters, found on the home screen of MODBUS protocol configuration (figure below), are defined as:
Figure 67: MODBUS RTU Slave Configuration Screen
Address and direct representation variables (%Q) to control relations and diagnostics:
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