Hi Dave
Not wanting to appear to be rude, but "crap". The discussion on the emc-users group was all about routing the step and direction signals via USB to a USB<=>parport converter. If it was a case of sending vector & velocity data to a smart controller, then I would concur that it is viable. As you point out, there are a number of devices now on the market that work. Why, there are even motion sub-systems to plug in to ethernet and CAN bus. BUT they all use vector/velocity or coordinate data and spit out the step/dir signals (for stepper motors). In effect, taking the high speed loop out of the PC and putting it into a smart controller. Regards, Paul. On Thursday 02 December 2004 16:16, turbulatordude wrote: > > We just went through this discussion on the emc-users group. �The > > general consensus was that USB parallel ports will not work because > > data > > > might be queued, thus messing up timing to the servo/stepper motors. > > Not all of us agreed, however. � � > > Simply put, they are wrong and you were correct. > > The entire project can be sent to a smart controller and just run > without the PC even being connected. > > Yes, e-stop and end switches then need to be in the controller. � > That's why is would have to be a smart controller. > > Also, data transfer can be buffered with 5 minutes of table time > being sent so the buffer has between 5 and 10 minutes of table > time. � Even Windoz would have a hard time messing that up. -- irc channel for EMC users at irc.freenode.org /join #emc Pieces of seven! Pieces of seven! (Hrm, parroty error) Addresses: FAQ: http://www.ktmarketing.com/faq.html FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/ Post Messages: [EMAIL PROTECTED] Subscribe: [EMAIL PROTECTED] Unsubscribe: [EMAIL PROTECTED] List owner: [EMAIL PROTECTED], [EMAIL PROTECTED], [EMAIL PROTECTED] Moderator: [EMAIL PROTECTED] [EMAIL PROTECTED] [EMAIL PROTECTED] [Moderators] URL to this group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO OFF Topic POSTS: General Machining If you wish to post on unlimited OT subjects goto: aol://5863:126/rec.crafts.metalworking or go thru Google.com to reach it if you have trouble. http://www.metalworking.com/news_servers.html http://groups.yahoo.com/group/jobshophomeshop I consider this to be a sister site to the CCED group, as many of the same members are there, for OT subjects, that are not allowed on the CCED list. NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BY POSTING THEM. DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO EXCEPTIONS........ bill List Mom List Owner Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
