On Sun, 2008-10-19 at 14:48 -0400, Greg Michalski wrote: > <snip> > So there is no default usage for each of the 12 outputs and 4 inputs?
Correct. HAL (Hardware Abstraction Layer) lets you "connect" EMC signals or "pins" to real pins as needed. > > I'm thinking about a 3-axis small mill with limit switches on the two > X and > Y axis plus spindle on/off and two coolants. > > Outputs > 3 Step and 3 Direction = 6 > 1 Common Enable, 2 Coolant and 1 Spindle = 4 > Total 10 outputs > Inputs > 2 Left Limit and 2 Right limit = 4 > Total 4 inputs. You can share the limits in different ways. One option is to wire the NC (normally closed) limit switches in series to one input. With this EMC2 will only be able to see a general limit event, but not know which limit. It should not be a big deal, but it's more convenient to have each limit sensed. Homes can be shared on one input also, but then you have to home one axis (joint) at a time. > > Will the .ini file allow this combination? > <snip> > > There is a "default", if you want to call it that, that the Stepconf > wizard starts with, and a couple "default" pinouts for off the shelf > control kits, but you can alter that to whatever suits your fancy so > the combination you mentioned (although for clarity by left/right I > assume you mean +/- for the limits on X and Y axes) would be possible. > If you add a second parallel port ($5-15 PCI card) then you can get a > little more advanced with its setup defining it as dedicated to be > mainly input or mainly output (mine is configured as mainly input and > IIRC it gives 12 inputs and 4 outputs - sufficient for me to > eventually implement a spindle tach and dedicated +/- limits and > homing switches along with a number of other expansion options). I > can't answer the Pico/Pluto question but I know both are decribed in > good detail in the documentation. I chose to design my own BOB as > opposed to a commercially available unit so I didn't have to abide by > any set pinout or other limitations. I tend to only use PCI parallel ports because they are cheap (even the double port cards, http://www.newegg.com/Product/Product.aspx?Item=N82E16815166007 ) and saves the motherboard port from my mistakes. > > I will add .02 though - your inputs don't mention anything about an > E-Stop input - I'd recommend adding that and running your limits in > series if you don't want to add a second parallel port. As mentioned elsewhere, an e-stop is recommended. I haven't researched this enough, but one e-stop feature is that the e-stop button should independently disable power supplies and drivers (I have a relay on the mains, my EMC2 PC is wired ahead of the relay so it stays on), and then the button should notify EMC2 of the event through an input. There may be other features to consider. > HTH - I'm sure someone will expand on the Pico/Pluto but read through > the docs and you'll probably see what is going on. > > Greg > www.distinctperspectives.com The Pico and Pluto-P controllers use the parallel port to pass data, rather than raw signals, to intelligence built into the controller, so the relatively slow signaling of the parallel port is much less of a factor. The controller has application specific firmware and hardware, so the I/O resulting from the data is much faster. I believe, typically a parallel port output can toggle at 20 to 30 kHz, whereas a controller can do 200 kHz or more. These controllers do cost more though. Kirk ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
