On Thu, 2009-12-10 at 21:31 +0000, Andy Pugh wrote: > 2009/12/10 Martin Pinkston <[email protected]>: > > > Andy, the 26 pin header pin out sheet is wrong. the Centroid guy saw a > > picture I took and told me I had a different board than what he initially > > thought should have been in this unit. > > Let me see if I can take a picture of the pin out schematic and post it on > > my blog. www.212steam.blogspot.com > > Aha! > > EMC can quite possibly drive that, but it is a little wasteful on > Parallel port pins. > > It needs to be unipolar for EMC to drive it, ie each motor phase wire > can only ever go +5 or 0v. Is it possible to check the inputs to those > terminals with a multimeter (with the motors stationary in a number of > positions as far as the software is concerned? Probably best checked > on the mating connector between the GND pin and each of the phase > pins. > If you see them alternating between 0v and 5v in a difficult-to-fathom > sequence then you ought to be able to use one of the other stepgen > types built in to EMC to drive the board. > Have a look at http://linuxcnc.org/docs/2.1/html/man/man9/stepgen.9.html, > especially stepgen types 9 and 10. > (and feel free to come back with any questions, of course). > > I am at a bit of a loss to know how to decide if your drive is bipolar > or unipolar. The motor lead count probably gives a bit of a clue. 4 > wires = bipolar, 5 or 6 = unipolar, more than that = anybody's guess. > > (And I am quite prepared to have someone more knowledgeable to shoot > me down in flames on any or all of the above)
I hope you don't mind more of my mental swarf, there's snow outside so I'm not too interested in doing any real work. Do we know if the driver board drives only one motor, therefore there are three of them. If that's the case, that supports the four phase input as opposed to my earlier guess at step/dir. If the orange resistor arrays are in series with the opto-isolators, an LED could be temporarily soldered on the two input pins of the 4N25's: http://www.fairchildsemi.com/ds/4N%2F4N25-M.pdf putting an LED in parallel to the opto-isolator LED. The LED's would then indicate the step sequence. Everything after that is already handled by the driver board, so unipolar bipolar might not matter. (For fun, it would be nice to get the numbers on the eight power transistors.) I wonder what the microprocessor is doing. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA ------------------------------------------------------------------------------ Return on Information: Google Enterprise Search pays you back Get the facts. http://p.sf.net/sfu/google-dev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
