Protocol

Modbus TCP

Lab ready Full lab

Modbus application PDUs carried over TCP port 502 with an MBAP header instead of serial address and CRC. Function codes and register maps match Modbus RTU; Unit ID still selects a logical backend slave behind a gateway. It is the default LAN path for many PLCs and energy meters.

Domains

Tags

scadaregistersport-502industrial

Sources

  • Modbus Messaging on TCP/IP Implementation Guide

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