Patrick Ferrick wrote: > Hello everyone, > > (First, I wonder how many British users of EMC saw the posts titled > "home-mad cnc" and thought....mad?...THAT'S for sure! :-) > > Anyway, here's what I'm wondering: if I wanted to get crazy and > control, say, six (or more) steppers with EMC, what's the best way to go > about that? I'm obviously not going to do it with a single parport. > Right now I have X,Y,Z and A going (and I'm thrilled to death with that, > believe me!) and that pretty much takes care of it. (To be specific, > I'm thinking about using a couple of extra steppers and solenoids and > such to make an automated tool changer.) > > Offhand I'm not even sure of how many axes EMC2 is willing to drive. > That would be nice to know... > > My first thought was a second parallel port card. I know that over the > years I have used (and, I think, fried) a couple of those guys...but I'm > pretty sure that with the shaky status of a _single_ "old school" > parport this is not a direction in which I want to be going. Then I > thought of one of those generic multi-I/O deals with huge numbers of ins > and outs, but that's probably (?) done by multiplexing fewer pins, which > I guess might be a problem for software that's trying to twiddle bits in > realtime for a particular effect. > > Any suggestions? > > Thanks! > > Pat
Well, it all depends. The standard parallel port actually provides 12 outputs, so if you don't have anything else (like spindle control, lube, coolant, etc) using them up, you could run two more motors that way. Another parport would let you do several more motors. And any high-pin-count I/O board would give you lots of outputs. There are a few cards out there based on 8255's or similar chips, and EMC has drivers for some of them. Another issue to consider is what you'll be doing with the extra motors. EMC's g-code dialect supports up to 9 axes - X, Y, and Z are the traditional linear axes, and A, B, and C are angular. U, V, and W are additional linear axes. But if you are doing a toolchanger or something, you probably don't want to be using g-code moves to manipulate tools. Instead, you might want to use a combination of ClassicLadder (software based ladder-logic PLC) and HAL components (including step generator) to execute a toolchange when EMC requests it, and then tell EMC when is is done. Regards, John Kasunich ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
