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8 May 2017

Windmill Software Ltd
Data Acquisition Intelligence
Call now: +44 (0)161 833 2782

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! Its extensive trouble-shooting capabilities make it ideal for solving comms problems, or for quickly checking that you can talk to your instrument before starting to automatically acquire data. The new version works with Windows 10 and earlier versions of Windows.

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

Download a Free Copy of ComDebug

ComDebug is free to our Monitor newsletter subscribers. Enter your e-mail below to subscribe and download the software.

ComDebug Features

  • No programming required
  • Free technical support for life
  • For instruments communicating over RS232, RS422, RS485, Modbus and TCP/IP
  • Understands ASCII, binary and hexadecimal data
  • For serial instruments that continually send data and those that need prompting
  • Quickly identify and correct communication errors
  • Insert cyclic redundancy checks (CRCs)
  • Send 4-byte (32-bit) integers, 4-byte words (double words), ASCII characters, hexadecimal, signed bytes, bytes, bits, 4-byte floating point, 4-byte reverse floating point…
  • Control the state of the PC's serial port output lines
  • See the state of the serial port input lines
  • See all bytes sent and received, even non-printing characters like carriage returns. This is crucial when dealing with binary data.
  • Send acknowledgements
  • For Windows 10, 8, 7, Vista, XP, 98 and 95
  • Data logging from one instrument.
  • Optionally, with the Windmill COMIML serial driver, continually send data from up to ten com or TCP/IP ports to the Windmill logging, charting and other data acquisition applications, or to other Windows software like Excel. The ComDebug download is packaged with a month's trial of the Windmill and COMIML software.

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. .

Free Technical Support for Life

Our software is so easy to use we offer free technical support for life. If you have a question the first places to look are in the program's Help file or on our Technical Support page. If you don't find the answer there then fill in our technical support form, fax us on +44 (0)161 833 2190 or call us on +44 (0)161 833 2782 (9 to 5 GMT or BST).

"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

The new software now also has a trouble-shooting screen, so you can see exactly what is being sent and received and identify where any problems may be occurring. The screen shows the outcome of each data reading, the messages sent and received, the data extraction procedure and result, and the time in hundredths of a second since data logging started.


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

* * * * * (1611 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 however there is information on how 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

Download ComDebug for Free

ComDebug is free to our Monitor newsletter subscribers. Monitor is a monthly newsletter giving data acquisition tips and techniques. It also features a regular Excel corner, explaining how to use Excel for data acquisition.

You will receive an e-mail asking you to confirm your subscription. On doing so you will be sent details of how to download the free software. If you don't receive this e-mail please contact [email protected].

You can read an archive of previous issues on our Newsletter page.