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RTU / TCP / ASCII Register Mapping CRC & Message Parsing

Frame Structure

← PDU →

01 1 byte

03 1 byte

00 01 00 02 4 bytes

95 CRC Low

CB CRC High

2 bytes

Full frame: 01 03 00 01 00 02 95 CB 8 bytes

← MBAP Header →

← PDU →

00 01 2 bytes

00 00 2 bytes

00 06 2 bytes

01 1 byte

03 1 byte

00 01 00 02 4 bytes

Full frame: 00 01 00 00 00 06 01 03 00 01 00 02 12 bytes

← PDU →

: 1 char

01 2 chars

03 2 chars

00 01 00 02 8 chars

B8 2 chars

CR LF 2 chars

Full frame: :010300010002B8C4\r\n 17 chars

Getting Started Learn by Example Deconstruct the address, function code, data, and checksum from 01 03 00 01 00 02 95 CB Start Learning

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