On 23 September 2013 00:22, Gregg Eshelman <g_ala...@yahoo.com> wrote: > The advice earlier about connecting the + terminal of each > drive input pin to +5V and connecting the BoB inputs to the - terminal > on the drives was, I think, good. That is how my drives need to be wired. > > *Tried swapping the + and - and it doesn't work.
That is not at all what I mean. The fact that the drives have + and - terminals for the step and dir inputs means that there are almost certainly opto-isolators on the inputs. These need to pass current for the internal drive electronics to see a step signal. (don't think in terms of the signals being voltages, once you have optos you are signalling with currents). First of all, that BoB needs a power supply. Do you have a USB cable plugged in to the USB port, or 5V supply to the connector near the USB port? This supplies a nice solid 5V and 0V for the BoB logic to work from. Then connect the 5V terminals (bottom left of the manual photo of the BoB) to the + terminal of each stepper drive. This provides the current source for the input optos on the drive. Connect the -step and -dir terminals on the drive to the step/dir pins on the BoB. Now download the parallel port tester program here: http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Parallel_Port_Tester You can now twiddle the pins directly and work out exactly which pin on the port connects to which terminal on each drive. You need to work out what pin value (on or off) gives 0V at the stepper drive - terminal. (because 0V at the - terminal and 5V at the + terminal is the current-flow condition, and indicates a step). Depending on whether the BoB inverts the pin values or not, this could be either way. If pin-off == 0V at the drive terminal then you need to invert the pin in stepconf. -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto ------------------------------------------------------------------------------ LIMITED TIME SALE - Full Year of Microsoft Training For Just $49.99! 1,500+ hours of tutorials including VisualStudio 2012, Windows 8, SharePoint 2013, SQL 2012, MVC 4, more. BEST VALUE: New Multi-Library Power Pack includes Mobile, Cloud, Java, and UX Design. Lowest price ever! Ends 9/20/13. http://pubads.g.doubleclick.net/gampad/clk?id=58041151&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
