Watch a Modbus device while it runs
Poll a set of tags continuously and see decoded values, response times and what the device is actually answering — the tool you reach for when a value looks wrong and nobody can say why.
Windows. Free for engineers — no account, no licence key.
What it does
Live values
The decoded engineering value beside the raw registers, refreshed at the polling interval you set for the server.
Register decoding
Change data type, byte order, scale or offset and see the same registers reinterpreted immediately.
Communication diagnostics
Response times, request and exception counters, and the quality of every register at a glance.
Trends and logging
Chart values over time and log them to CSV, Excel or SQLite for a report.
Background reading
Modbus 40001 addressing explained
Why the manual says 40001 and the software asks for 0, where the off-by-one comes from, and how to tell which convention a document is using.
Modbus float byte order
A 32-bit float spans two registers and vendors disagree about the order. ABCD, BADC, CDAB and DCBA, and how to identify which one a device uses.
Modbus exception codes
What each exception response means, what usually causes it, and how to tell an exception apart from a timeout.
Moving from testing to production?
When the device is understood and the data needs to go somewhere continuously, Edge Gateway turns the same tag map into a deployed runtime.