> > I have two VFD's (a pDrive MX eco and a Toshiba VF-S11) both of which > are Modbus-capable and I'd like to integrate into Emc. I've read the > GS2 VFD driver, and adapting this good example would be an option. It > seems Modbus integration comes up frequently though. > > I'd be curious what people think about a generic userspace hal > component to deal with different Modbus devices (without going through > ClassicLadder), and what would be good design choices to map Modbus > read/write commands to signals and parameters in a generic fashion. > > On an abstract level, I'd see a parameter being mapped to one or > several register writes, possibly with some arithmetic and boolean > expressions applied; on the input side: certain registers or 'coils' > being read, fed through expressions and resulting in signals. A > generic, configurable python component might be an option.
While I see nothing wrong with creating a stand alone general modbus component I don't see the value in adding expressions or boolean to it. Adding invert would be fine. If you want to do fancy math to the signals - use Classic Ladder or use HAL components after the fact. I say this mostly because of the complexity it would add. There is enough complexity with just all the variations in modbus. I would think using a XML format config file would be good - you could add a GUI to it later. Actually the GUI is why Classicladder is handy, Though The GUI and the modbus routines still need work. I intend to change it to use the modbus routines that GS2 uses but am currently working on something else. > > Is it worth the effort? or should I just go ahead and adapt the gs2 > driver for each component? That is really up to you ! personally I would use Classicladder or adapt the GS2. Depends if you are interested in doing the programming or want to give something useful to EMC. My 2 cents worth Chris Morley _________________________________________________________________ Experience all of the new features, and Reconnect with your life. http://go.microsoft.com/?linkid=9650730 ------------------------------------------------------------------------------ Crystal Reports - New Free Runtime and 30 Day Trial Check out the new simplified licensign option that enables unlimited royalty-free distribution of the report engine for externally facing server and web deployment. http://p.sf.net/sfu/businessobjects _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
