Modbus Test Software available?

M

Thread Starter

Mark Schears

I am developing Modbus ASCII and RTU into a product, running on a RS-485 network. Are there any programs available that would act like a Master and send/receive packets to/from my slave device?
Thanks
 
I'd recommend using a protocol analyzer in addition to the mock master. I was able to find both as shareware on the internet a few years ago, but you will also need to find a RS485/RS232 converter to connect the serial port from your PC onto the RS485 line. The protocol analyzer is invaluable because you will be able to see the raw serial traffic on the line, allowing you to verify the master is sending correct requests and the slave is responsing correctly. Try "www.modbus.org":http://www.modbus.org or I recently saw one at "www.imperioustech.com":http://www.imperioustech.com .
 
B
There are some shareware programs. One is called "CALC" and another is from MTS. Both are old and DOS environment progs. Try local Schneider (Square D) office for copy.

Absolute best Modbus simulation/test s/w is from CALTA, located in Calgary Alberta Canada. Phone 403 252 5094. Or "www.calta.com":http://www.calta.com .
 
The MatPLC has a Modbus Master module, including both ASCII and RTU (and TCP). Unfortunately the documentation is not quite there yet, so you'll have to ask on the list or take guidance from the modbus demo (there's extensive comments in the matplc.conf file).

Let me/us know if you intend to use it, I'll see if I can put up at least a draft of the relevant part of the manual up on the web.

The advantage of MatPLC is that it's free and open-source, so you can add extra debugging output to it and otherwise see more of what's happening.


Jiri
--
Jiri Baum <[email protected]> http://www.csse.monash.edu.au/~jirib
MAT LinuxPLC project --- http://mat.sf.net --- Machine Automation Tools
 
Yes, Wintech has some good tools to "try some things" - ideal for testing & site work. But it still only does "positive" (correct) things.

So this would be an ideal "project" for anyone looking to do a good shareware which has value and wants to earn a name for themselves.

- Create a good Modbus/RTU, Modbus/ASCII, and Modbus/TCP negative test tool. Test all the size boundaries, test bad CRC, test too-slow and ultra-fast responses, test unmatched responses (ie: poll slave #4 and have slave #7 reply) etc.

Best regards

Lynn August Linse, Senior IA Application Engineer
15353 Barranca Parkway, Lantronix Inc, Irvine CA 92618
[email protected] www.lantronix.com
Tel: (949)279-3969 Fax: (949)453-7152
 
Lynn Linse wrote:
> Yes, Wintech has some good tools to "try some things" - ideal for testing
> & site work. But it still only does "positive" (correct) things.

> So this would be an ideal "project" for anyone looking to do a good
> shareware which has value and wants to earn a name for themselves.

> - Create a good Modbus/RTU, Modbus/ASCII, and Modbus/TCP negative test
> tool. Test all the size boundaries, test bad CRC, test too-slow and
> ultra-fast responses, test unmatched responses (ie: poll slave #4 and
> have slave #7 reply) etc.

The MatPLC project ( "http://mat.sf.net":http://mat.sf.net ) might be a good start for that - it supplies source code and allows redistribution.

The Modbus module is implemented in two layers, too, so it should be relatively easy to add the testing stuff to the upper layer and have it
automatically appear in all three versions (RTU, ASCII, TCP).

Jiri::
--
Jiri Baum <[email protected]>
http://www.csse.monash.edu.au/~jirib
MAT LinuxPLC project --- http://mat.sf.net --- Machine Automation Tools
 
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