Download Serial Communication
and Data Logging Software

Windmill ComDebug: serial communication software lets you log data from almost any instrument connected to your PC's COM or TCP/IP port.

The ComDebug program communicates with RS232, RS422, RS485, Modbus and TCP/IP devices. What's more, it's free! It logs data from a device plus its extensive trouble-shooting capabilities make it ideal for solving comms problems.

Features | No Programming Required | What devices can you read with ComDebug? | Monitor Serial Communications | Technical Support | Comments | Download a Free Copy of ComDebug

Download a Free Copy of ComDebug

ComDebug is free but we offer no technical support or after-sales service with it. If you need help using it click the program's Help button or see this web page.

ComDebug Features

No Programming Required

Simply select your communication settings or type your instrument's commands: no need for any programming.

Serial Communications Software

The new custom commands allow ComDebug to extract data even if it is an unusual format. For example, the start of a message might be indicated by only part of a byte whilst the rest of the byte carries data. By entering a custom command, ComDebug can log the just data and ignore the rest. Users can enter custom commands themselves, or Windmill Software are happy to set up a custom command for any instrument.

What sort of Devices can you Read with ComDebug?

With ComDebug you can control both those serial devices that continuously output messages, and those that require commands before supplying data. With a flexible approach to building command strings, and parsing the received data strings to extract data values, the majority of analytical instruments are supported. These include altimeters, balances, conductivity meters, data loggers, dial gauges, digital indicators, digital thermometers, DMR, extensometers, flaw detectors, flow meters, fluorometers, force gauges, gas analysers, GPS, gyro compasses, hygrometers, I2C devices, ion gauges, load meters, motion sensors, multimeters, myographs, oxygen electrodes, particle analysers, pH meters, PIC microcontrollers, plcs, pressure transmitters, power analysers, RLC meters, RFID readers, thermoregulators, titrators, solar panel array controllers, sonar and water baths.

ComDebug reads data from many instruments, including multimeters

You have the freedom to mix and match equipment from many different manufacturers in many combinations. For example, serial devices from Acculab, A&D, Advantec, Ashtec, Avery Berkel, B&B Electronics, Bruël & Kjær, Campbell Scientific, Crosstalk Security, Dataq Instruments, Daily RFID, Dataq Instruments, Datel, Datataker, Denver, Desoutter, Ecom, Fisher, Fluke, Funaro, Garmin, Geolux, Honeywell, Horiba, Humminbird, ICP DAS, Keyence, LOVATO electric, Love Controls, Linkcom, Magellan, Maxim, Mettler Toledo, MecMesin, Metrix, Microchip Technology, Mitutoyo, Motorola, Molytek, Newmar, NovAtel, Nu-Metrics, Ohaus, Omnistar, Omron, Orion, Panametrics, Parallax, Parker, Phytron, Protek, Quantum Logic, Remontec, Rockwell, San Jose, Sartorius, SecuMaster Technologies, SG Brown, Siemens, Sokkia, Sylvac, Telegan, Texas Instruments, Transcell, Tritech, TTi, TSS, Turner Designs, Varian SenTorr, Veris, Vitrek, Voltcraft, Weeder Technologies, Weilheimn, WTW, World Precision Instruments and YSI have all been handled by Windmill. Many channels of data can be accepted from each instrument.

"I would recommend ComDebug to any one who has to trouble shoot a serial card problem. I used it to locate a defective com card which the manufacturer said could not be."
Doyal J. McVicker Jr.
"Your software works great; it's the only package that allows me to set the DTR line low...required by the TI (Texas Instruments) development board configuration."
R E Rogers
"ComDebug solved a problem I had debugging Phytron motor controllers"
J Stirling
"ComDebug helped me solve an HP-IL to RS-232 interfacing problem."
M O Tjebben
"Used it to simulate the data output of a Resistance Weld Control into our Web enabled PLC."
J Franks
"This is a great tool for reading the ASCII commands your DVR is sending."
Crosstalk Security Inc

Monitor Serial Port Communications

Monitor serial port communications: see the state of input and output lines
With ComDebug you can see the state of the serial port input lines and
control the state of the PC's serial port output lines.
For details of what each line does see our RS232 connections page.

Send commands and data to serial instruments and view replies
The Terminal screen lets you send commands and data to the instrument,
and view the reply. For those instruments that require it,
you can send an acknowledgement when the reply is received. .

Technical Support

We don't offer any technical support for the free software. If you have a question look in the program's Help file or on our Technical Support page.

"ComDebug is so easy to use I have not needed to read anything."
RT, Reservoir Engineering Specialist Oil and Gas Production - Research. Using ParoScientific Quartz pressure transmitter.
"Great Software!"
GH, Audio Systems Engineer using Audion Precision System Two Cascade.
"No problems, it did exactly what I wanted it to do."
SM, Electrical Engineer performing tests on a Modbus Variable speed drive.
"Outstanding little tool! Best freebie I've ever seen! No problems, it worked perfectly."
JF, Industrial Control Engineer.
"No problems, ComDebug is a great resource."
iDA, Mineral Chemistry (Quantitative).
"Fantastic tool for debugging"
Rajesh Bhor


Have you used Comdebug - what do you think? Any questions? Let us know.

* * * * * (135 users, 4.9)



"I have recently changed computers and wish to download the latest copy of comm debug. I have subscribed to your magazine for many years and use comm debug with great success. I have subscribed once again and received the confirmation email to download this great program...I am happy for you to use my comments, a good product needs a good reference"
Donald Peck, Napier, New Zealand
"Excellent software...very helpful"
"Awesome little tool"
Ebik Sharma
Ibrahim El Sayed, Senior Biomedical Engineer at ZEISS Group