Modbus Exception Response Code Decoder
Decodes Modbus exception function codes and standard exception error meanings.
Notice: engineering verification utility. Use test or de-identified data and verify results independently before relying on them.
How it works
Standard: Modbus Application Protocol Specification v1.1b3
Formula: Exception Code lookup (01: Illegal Function, 02: Illegal Data Address, 03: Illegal Data Value, etc.)
Checks: Valid exception code range (01 to 0B)
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Deterministic local-first client-side execution. Provided as-is without warranty.