In parallel with the development of data transmission in the telecommunications sector to connect peripheral devices, hardware engineers have defined interfaces for independent communication systems. The basic idea of having standardized interfaces for external devices was quickly extended to control and instrumentation equipment, as the real-time characteristic of distributed systems became a challenge in the field. The proposed Modbus Extension (ModbusE) builds on these new techniques introduced in the UART interface, so that the newly introduced extension retains all the characteristics of the Modbus RTU except for the character bit structure. The validation of the ModbusE protocol allowed the proposal of a new communication message structure, a description of Modbus devices, an acquisition cycle to attain a deterministic temporal response behavior and the definition of an architecture for IIoT integration. In this work, practical research is based on data update times in SMARTConvert software when between 1 and 50 registers are accessed. These registers can, in the most favorable case, be at consecutive addresses and can all be read in a single bus query request, or at addresses 1 to 50, or the registers must be read in separate requests. The contributions of this paper are related to highlighting cases where Modbus modules are incorporated, the addressed registers are not consecutive and the Modbus reads 1 or more holding register records and the ModbusE proposal. As these registers must not be on consecutive addresses, it is necessary to make several requests, defining the function of a Modbus acquisition cycle, adapting the equations to the purpose of the tests carried out, measuring the Modbus communication signals and describing the ModbusE communication concept.
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