Hi Wayne On Sat, 31 Mar 2007 15:24:54 +0100, "Enhanced Machine Controller (EMC)" <[email protected]> said: >Hi all. > >Been looking a little into EMC2 and in the next week will be able to >compare it to the software I currently use on the VMC (mach). > >I do really want to get away from Parallel ports and maybe even step/dir >drives. I try not to use steppers under any circumstances. > >My biggest major project is my Hardinge HXL-S CNC lathe which has been a >long battle to get as far as I have got with limited time available. I >also have two gang tooled lathes in the queue. > >Anyways, had a quick look at the boards supported by EMC2 and it does >seem that they are all passive devices ie not motion controllers per se >as say a DeltaTau or Galil card would be. But rather convenient i/o cards.
We tend to think in terms of "dumb" io as opposed to "smart" cards. Dumb io passes signals directly through to the PC where smart io tends to process stuff on the card. The Galil or DeltaTau boards are "smart" to our way of thinking because they take a high level set of signals and produce motion from them. >Do they offer performance advantages over the parallel port other than >the additional i/o available? If by the term "they" you are referring to dumb cards, they offer the advantage of many more signals than you can get from a single parport. There is no speed advantage of say a mesa or vital or ... over a parport because the speed can be handled by emc's thread timing. >Is it likely that EMC2 will support so called intelligent motion >controllers? I don't know any reason we would want to. We use the PC to handle motion planning and such that the intelligent boards do. If we were to build an EMC for galil for example it would be little more than an interpreter and some sort of task/canon reader that translated it's input into the galil language. >Any intention to support external PLC's over modbus? Again our thinking has been, "why spend the money for an external processor when the PC can also handle these tasks. That's why we have a logic processor working in the emc environment itself. >What would the experienced emc2 guys here suggest as far as the type I >should use for the lathe above as an example? > >Currently it has new servo motors (brushed) and drives (step/dir input) >but the machine also needs a load more i/o for the other systems on the >machine. It has a 1024 lpr encoder on the spindle which I would like to > exploit rather than just an index signal. We chose Pico stuff for the last lathe I worked on. It was simply a matter of price for the combination of real servo drives, real feedback to the PC and just a bit of "smarts" on the Pico interface cards. It should easily handle the setup you have described here. Oh and did I mention that it produces a fully closed loop servo system! >I know how I would do it with Mach, but emc2 is not quite the same ;) That is a truth! Pico tried to get their drives and interface cards supported by Mach but to date they have been unsuccessful. My advice on how to proceed. First study a bit about EMC2 by downloading and building a PC with the Live CDROM. Start up emc2 and look around a bit at the Hardware Abstraction Layer. That install also gives you a couple of manuals that you can have a look at for further info. Second is to get yourself hooked into the comm networks, lists and ircs. Third remember that "we" are a collection of unpaid folk who are working here for mutual benefit. If all what you want to do is make chips using EMC2, you might consider hiring a consultant. If you choose the consultant path, a note here to that effect should get several interested folk. Rayh ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
