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Modbus Serial Plugin Issue
« on: June 15, 2014, 07:34:13 PM »
I've been using modbus for a few years but now have the need to read a DWORD (16 bit).  I've always ued the non-plugin setup which always worked great.  I recently tried the plugin version because it seems like it may be easier to deal with a 16 bit number.  Here's the issue.  When I disable the plugin and bring up the standard modbus setup screen, I can go to the test screen, enter addresses and such, hit read and it works.  When I enable the plugin and go to the test page all I get is a timeout.  The port is connecting properly, just timing out.  If I disable the plugin and go back to the standard setup, it all works again.

Does anyone have any ideas?  Or possibly an in-depth explanation of how to set up modbus using the plugin?  I've been through the videos and everything else I could google to no avail.

Thanks
Re: Modbus Serial Plugin Issue
« Reply #1 on: June 16, 2014, 05:02:32 AM »
Hi,

Attach a screen dump of your serial modbus plugin setup screen and your legacy modbus setup screen and I'll have a look and see if I can spot anything.

Cheers,

Peter
----------------------------------------------------
Homann Designs
http://www.homanndesigns.com
email: peter at homanndesigns.com
Re: Modbus Serial Plugin Issue
« Reply #2 on: June 16, 2014, 08:16:36 PM »
Thanks Peter.  For some reason when I went back in to take some screenshots, it was working, which I can't explain.

I have something else related though that you may be able to help with.  The slave is a DL06 PLC.  It is doing some calculations with the real data type.  It is producing anything from 0 to 2.6 out to 3 decimal places.  I need to bring that into Mach3 over the Modbus.  I think the problem is that Mach3 doesn't recognize the real numbers.  Would you know either get the real numbers into mach3 or what to do with them on the PLC side?

If I format the numbers in the PLC to BCD, they come across coreectly in Mach.  I don't think I can convert a real, which is a DWORD, to a BCD, which is a WORD. 

Thanks
Re: Modbus Serial Plugin Issue
« Reply #3 on: June 16, 2014, 09:04:18 PM »
Hi,

Good to see it working.

In the PLC, multiply your value by 1000. Your value will then be from 0 to 2600. You should then be able to put it into a WORD (16bits). Then transfer this to Mach3.

Cheers,

Peter
« Last Edit: June 16, 2014, 09:06:10 PM by Peter Homann »
----------------------------------------------------
Homann Designs
http://www.homanndesigns.com
email: peter at homanndesigns.com