Modbus RTU / Modbus TCP

Modbus Simulator

Simulate Modbus RTU and TCP devices without touching real hardware

↓ Download for Windowsv0.1.0 · 48 MB · Windows x64 · all releases

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The Modbus Simulator running as a TCP slave: a register table with holding registers 40001–40006 populated, and a live traffic log showing incoming read and write requests with decoded values and raw bytes.

Overview

Why this exists

Commercial Modbus simulators are capable but closed-source and licensed per seat — which is a real barrier when you just need to check that a register map is right before a site visit. OpenBench’s Modbus Simulator does the same job, free, with the source code open for anyone whose company requires audit-ability before installing new tools on an engineering workstation.

Spec sheet

▸: Slave (server) and master (client) simulation modes
▸: Configurable holding registers, coils, and discrete inputs
▸: Live register read/write log, exportable as CSV
▸: Modbus RTU over serial and Modbus TCP in one tool
▸: No license key, no telemetry, source available for audit

Requirements

— Windows 10/11 (Linux build planned post-launch)
— A serial port or virtual COM port for RTU mode

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