On Mon, 2009-04-27 at 01:12 +0200, Haberler Michael wrote: > Hi > > 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. > > Is it worth the effort? or should I just go ahead and adapt the gs2 > driver for each component? > > -Michael > > I am a newbie in automation bus matters, but I'd assume other control > software has the same problem (plus dealing with other buses).
I briefly worked on a HAL component to use Modbus with my Hitachi SJ200 VFD. http://www.wallacecompany.com/machine_shop/EMC2/modbus/ I could be off base here, but it seemed to me that different VFD's didn't have enough in common to warrant the extra effort to have one driver or component cover all Modbus devices or even Modbus VFD's. I recently did a search on a Mutibishi VFD which indicated Modbus and CC-Link compatibility, but apparently you could only monitor the VFD status with Modbus. CC-Link was needed to make any parameter changes. Researching CC-Link exposed me to a bunch of other industrial standards that VFD's might use. So a generic Modbus or VFD driver might be difficult. What might be good, is documentation that would make it easier for a user or manufacturer to write their own. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA ------------------------------------------------------------------------------ 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
