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Re: Problems with Modbus TCP
« Reply #10 on: February 17, 2014, 07:45:56 PM »
Hi,

The other problem you may be experiencing is that some USB to RS232 converters will fill their buffer, then transmit the data in a burst.

This can result in the Modbus inter- message gap being destroyed, resulting in CRC errors.

Cheers,

Peter
----------------------------------------------------
Homann Designs
http://www.homanndesigns.com
email: peter at homanndesigns.com
Re: Problems with Modbus TCP
« Reply #11 on: February 17, 2014, 10:24:25 PM »
I guess I missed the USB to Serial converter reference in Scott's post. I don't have USB, my converter is Serial 232 to Serial 485.  On the 485 side, I have screw connectors that take me to the Modbus 485 to the drives and touch screen.  The problem would either have to be in the serial 232 card in the PC or the 232 to 485 converter.  My next step is to reduce the baud rate and see if that solves it.  The other thing could be Modbus 485 is normally terminated on both ends.  I don't have any terminations because it's a very short run and all three slaves spur from the same connection point.  Nothing is more than 10 feet.

Thanks
TeaMan
Re: Problems with Modbus TCP
« Reply #12 on: April 15, 2014, 01:12:11 PM »
No worries TeaMan, your not robbing thread.  So were you able to get anywhere with your Drive?  I forgot about the thread and now that my table is back up and running I am now talking the drive setup again.  If you have any insight that might help me, it would be greatly appreciated.
Re: Problems with Modbus TCP
« Reply #13 on: April 15, 2014, 07:25:41 PM »
Yes I did.  I got help from various members, mostly Scott, Poppabear.  He was great to work with and really knows brains and Modbus.  I had various issues from addresses to converters to brains but got it all worked out.  Let me know where you are in your project and what issues you are having and I'll see if anything I learned will help you.  Others may be able to help also.

Ed
Re: Problems with Modbus TCP
« Reply #14 on: April 16, 2014, 07:57:34 AM »
Well I have just started back at this project.  I am running a Emerson Sk Commander drive with a sm-ethernet module.  This module allows me to communicate over Modbus /tcp or ip.  I did talk to a programming buddy at work with me and said he can help get the control words and parameters setup.  But he can't help with the mach3 brains or macros.  I think I have a mental block when it comes to the brains or macros.  Do you have a layout of the brains that I can look at and decipher.  rive is different but may help me in the right direction.  My programming friend one problem I had was that I never dropped the indicators into the Sm module so that the drive new what the master was sending.

My ultimate goal is to start, stop spindle and control speed.  Hoping later to control vacuum table  dust collector, and various other things.  But first thing is first communication.  I appreciate any help you have.  I did attach sm -module manual of my drive if you want to look at it.
Re: Problems with Modbus TCP
« Reply #15 on: April 18, 2014, 09:44:28 PM »
On the Mach3 side, you basically have to do two things.  First, you have to go into Function Configs and go into the setup Modbus tcp.  What I did was set one config for each address.  If you have more than one address that are next to each other, you can combine them, but I didn't, it made it easier to remember what I was using in my brain.  I then set up a brain to do just what you are trying to do.  It was to start and stop the motors, change direction, and set the speed. Here is the code in my brain.  Hope this helps.
Re: Problems with Modbus TCP
« Reply #16 on: April 19, 2014, 10:41:29 PM »
Thank you.  I have gotten further. I was able to test commands through the modbus test.  That was exciting.  I did see your attachment though.
Re: Problems with Modbus TCP
« Reply #17 on: April 21, 2014, 05:01:54 PM »
Just wanted to give everyone an update.  I have gotten further with the SK emerson drive.  It was a bit confusing but I have some good news.  Mach3 will communicate via modbus TCP, you just have to do some moving of parameters within the drive.  If anyone needs the these Parameters just let me know.  I have tested the stop and start via command designated by Emerson controls.  Like forward, stop, and reference select.  Now I am off to try and put this in a brain.  It has deffinitely been a bumped road but I think tha tlight is starting to flicker at the end of the road.  Does anyone know if Modbus TCP and be ran within VB script or Macros?  Or am I only able to use Brains?  Thanks everyone that has helped thus far.
Re: Problems with Modbus TCP
« Reply #18 on: April 22, 2014, 09:20:57 PM »
Sorry the brain didn't attach.  here is one more try.  I went with the brain mainly for speed.
Re: Problems with Modbus TCP
« Reply #19 on: May 02, 2014, 12:12:28 PM »
Ok I was able to communicate via mach3 over TCP Modbus.  I got one line in brain and it works.  Yaay.  Now I have to figure out how to command the drive to turn cw when spindle on when it's instructed and then send another command to stop spindle for tool change or do program.  I guess that's where Invert comes in? 

So far this is what I have.

Spindle CW On ->  No-OP  ->  Formula A* 131  ->  Mod: 0-T:0