Modbus RTU Online Debug Tool | All-in-One Tool for Serial Port/Data Collection/Parsing/Visualization

Modbus RTU online debugging tool, supporting direct serial port connection in browser, real-time data collection, multi-format data parsing (binary/text), data visualization and export. Supports various data types (UINT16/INT16/UINT32/INT32/FLOAT32) and byte orders (ABCD/DCBA/BADC/CDAB), can be used with Modbus RTU tools for complete device debugging process.

Serial Configuration

Baud Rate
9600
Data Bits
8
Stop Bits
1
Parity
none
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Log Information

Max Lines
Display Format
HEX
MS

Modbus Data Parser

Data Source
Serial Data
Data Format
Binary
Enable Parsing
Slave Address(HEX)
Function Code(HEX)
Rule NameStart PositionData TypeByte OrderCoefficientConstantDecimal PlacesActions

Data Table

Max Lines
IndexTime
No data
No data

User Guide

Overview

Modbus Debug Tool is a powerful serial communication and data parsing tool specifically designed for Modbus RTU protocol debugging and data analysis. It helps users quickly establish serial connections, send Modbus commands, and parse received data in real-time.

Main Features:

  • Serial Communication: Supports various baud rates and serial parameters for reliable communication with Modbus devices
  • Data Monitoring: Real-time display of sent and received data, supporting both HEX and text display modes
  • Data Parsing: Powerful Modbus data parsing functionality, supporting various data types and byte orders with customizable parsing rules
  • Data Visualization & Export: Parsing results can be displayed in both table and chart formats, allowing real-time trend monitoring and Excel export for further analysis

Using with Modbus RTU Tools

  • Command Generator: Use the command generator on the Modbus RTU tool page to quickly generate standard Modbus RTU commands, copy to sending area for direct use
  • Data Generator: Use the data generator on the Modbus RTU tool page to generate test data for testing parsing functions without actual devices
  • Typical Workflow:
  • 1. Configure serial parameters and connect device
  • 2. Use command generator to create needed Modbus commands
  • 3. Configure timed sending for automatic data collection
  • 4. Set up parsing rules to view results in real-time
  • 5. Monitor data changes using tables or charts
  • 6. Export data for offline analysis when needed

Serial Configuration

  • Click select serial port button to choose the device to connect
  • Baud Rate: Commonly 9600, 19200, etc., must match device settings
  • Data Bits: Usually 8 bits
  • Stop Bits: Usually 1 bit
  • Parity: Usually None

Log Configuration

  • Display Mode: HEX (hexadecimal) or TEXT mode
  • Auto Clean: Automatically clean old data when exceeding maximum lines
  • Max Lines: Maximum number of log lines to retain

Send Configuration

  • HEX Mode: Send data in hexadecimal format
  • Append CRLF: Add carriage return and line feed at the end
  • Cyclic Send: Repeatedly send data at set intervals
  • Send Interval: Time interval for cyclic sending (milliseconds)
  • Modbus RTU Command Examples:
  • 01 03 00 00 00 0A C5 CD - Command to read 10 registers
  • 01 10 00 00 00 01 02 00 01 67 90 - Command to write 1 register

Modbus Data Parsing

Data Source

  • Serial: Real-time data directly from device
  • File: Data read from saved data files

Data Format

  • Binary FormatRaw Modbus RTU data output directly from device
  • Text FormatSpace-separated hexadecimal text, e.g.: 01 03 0C FF FF DE F2 FF FF F1 0D 00 01 3B 3C B5 40
  • Note: Data format can be selected regardless of data source. For example, if serial port receives text format, select text format for parsing

Parse Rules

  • Start Position: Starting byte position in data area (0-based)
  • Data Type: Supports various numeric types (UINT16, INT16, UINT32, INT32, FLOAT)
  • Byte Order: Byte sequence for multi-byte data (ABCD, DCBA, BADC, CDAB)
  • Coefficient: Multiply parsed value by coefficient (default 1)
  • Constant: Add constant after applying coefficient (default 0)
  • Decimal Places: Number of decimal places to show in result
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