Well now. . . If I wanted to set up a Proview Scada system (http://www.proview.se/) with some autonomous material handling robots here and there, this modbus slave feature might just come in very handy. Just for a bit of interlocking, nothing fancy. So speed is not at all important, neither is advanced data handling.
Or even for communication with an advanced toolchanger setup with an extended toolstore. A single station LCNC (EMC) will be totally lost without a dedicated tool exchange computer in such cases. And why must LCNC poll the toolchanger contimually, there might just as well be a second channel where the toolchanger is the master. My 1/2 cents (SouthAfrican) worth. j. On Mon, Feb 27, 2012 at 7:37 PM, Chris Morley <chrisinnana...@hotmail.com>wrote: > > > > > > > Yes, Modbus doesn't seem to want to die and is handy for VFD's and > > PLC's. The point I was try to explore is why LinuxCNC has a slave > > feature as well as the master feature. VFD's and PLC's are slaves and > > provide services to LinxCNC, so why would I want to have LinuxCNC be a > > slave? This could allow two LinuxCNC PC's to talk to each other, but I > > would think there are easier ways to do this. I think the feature is > > there because it is part of the Modbus package and got a free ride. It's > > no big deal, I was just curious, but I might want to give it some > > attention if someone is actually using it. > > > > I use Modbus with VFD's and some time in the future maybe an AVR tool > > changer controller, others use it with PLC's. My plan so far is to keep > > any focus I may have on those items. > > -- > > As was mentioned Modbus master/slave is incorporated with Classicladder. > Version 7.100 (the first version included in EMC2) actually had Modbus in > the source - it was just turned off. > When I updated EMC2 to the 7.124 version, I decided to include it. > > I personally never got the slave version to work but that is probably > because > I don't understand TCP connections. > Do you connect two computers with crossover cable or must you use a router? > How do you find the address? > > Marc (Classicladders creator) tells me he has tested it and it worked. > He just never supplied step by step instructions. > > I can see no reason not to have a slave feature. If you have a separate > computer > you could use it as a smart PLC without slowing down your main computer. > or have the second computer run windows (CL runs in windows too) > The original CL was made to be able to be included in embedded machines. > > Also it would allow you to test your Modbus connection which is probably > why > Marc coded it. > > If you figure out how to use it please add it to the official docs. > > Chris M > > > ------------------------------------------------------------------------------ > Try before you buy = See our experts in action! > The most comprehensive online learning library for Microsoft developers > is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, > Metro Style Apps, more. Free future releases when you subscribe now! > http://p.sf.net/sfu/learndevnow-dev2 > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
