Hi I speak as a relative ignoramus of EMC2..
However, I think the real world issues that will turn round and bite you were mentioned by John K. Executing a file of G-codes is straightforward, jogging, implementing a responsive feedhold, feedrate override, homing, respecting limits before the nut falls off the end of the screw, probing are not straightforward and all have realtime aspects. IMO Mach3 which has tried this path (and is of course a naturally buffering controller) is at its most capable and responsive then using the parallel port and letting the PC do all these things. Implementations using GRex/G100 and ncPOD (q.v.) (Ethernet and USB interfaces respectively) liberate the PC but give usability compromises. On a different tack - a laptop is not really a very good computer for machine control. Relatively fragile and not modular (key boards don't like my workshop), more expensive per MegaFLOP (or whatever you like to measure). So parallel ports or PCI boards like the Mesa ar not such a limitation. Best wishes John Prentice ----- Original Message ----- From: "Till Harbaum" <[EMAIL PROTECTED]> To: "John Kasunich" <[EMAIL PROTECTED]>; "EMC developers" <emc-developers@lists.sourceforge.net> Sent: Monday, April 23, 2007 4:49 PM Subject: Re: [Emc-developers] DIY USB interface >> I didn't think of that approach. But it basically means discarding >> EMC's motion controller and writing a new one inside the USB device. >> The EMC motion controller (including trajectory planner) is the result >> of years of work, and would not be trivial to replicate. > And it isn't what i intended to do. I'd prefer to decouple the motion > controller from its fixed clock. > > The simulator must be doing something similar as it still uses the > motion controller and runs at some "magic" rate. > > Till > > ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
