ComTest Pro is a communication test software for MODBUS RTU Devices via Serial and Ethernet. This complementary program allows users to test and troubleshoot MODBUS RTU communication by sending single or multiple read or write commands to the device. The software offers comprehensive data-logging, data-formatting and error checking features.

Features:
1. Serial communication baud rates up to 230.4K
2. Support for MOBUS TCP and MODBUS RTU over Ethernet
3. Decimal/Hexadecimal logging
4. Read Holding Registers (0x03) w/ customizable function codes
5. Write Single Holding Register (0x06) w/ customizable function codes
6. Write Multiple Holding Registers (0x10) w/ customizable function codes
7. Detailed logging with date and time step
8. Write function support for up to 128 data registers
9. Read function support for up to 128 data registers
10. Raw data view selectable Hex/Dec
11. Read or Write a range of user specified registers
12. Read or Write registers auto-color for valid and error response
13. Loop / Repeat Command
14. Advanced Error Checking Dialog
15. Independent Valid, Error and Time-Out counter with reset function
16. Save log file in text or rich text format (color coded)
17. Valid Response Counter with independent Reset Function
18. Error Response Counter with independent Reset Function
19. Time-out Response Counter with independent Reset Function
20. Error message suppression function
21. Comprehensive error checking
22. Adjustable Response Delay Time
23. Adjustable Transmission Delay Time
24. Selectable RTS Control Selectable
25. Selectable Echoback Suppression
26. Reverse CRC Support
27. Comprehensive Help File
28. Automatic Update Function

This program allows the user to test Modbus communication from a standard PC to any type of Modbus compliant device using either a serial (RS232, RS422 or RS485) or Ethernet (Modbus TCP or Modbus over TCP) connection. This program consists of a user friendly interface that allows the user to test communication quickly and easily. When the program is first started the main screen appears.

The first step involves setting up communication with the attached device through either serial or Ethernet. The second step involves entering the correct device and register addresses and then selecting the command to issue to the device. The third step is where all testing takes place and includes a view of register values that were read, register values that are to be written, raw Modbus data as sent and received from the device, and finally a log.

The license of this software is Freeware, you can free download and free use this network utility software.