On 12 August 2015 at 09:37, John Dammeyer <jo...@autoartisans.com> wrote: > The lack of a spindle input or PWM output on the Probotix cape and the > higher price of the PMDX cape rules out the Beagle for any sort of Linux CNC > at the moment. That and what appears to be a lack of continuing support for > the Beagle and LinuxCNC.
I think you may be misinterpreting the situation. Machinekit seems to be committed to the Beaglebone, and the Machinekit flavour of LinuxCNC will work just as well as old-school LinuxCNC with a lathe. All you need to do is set up one of the step generators in the PRU in velocity mode and connect then "net spindle-speed motion.spindle-speed-out-rps => ****.stepgen.02.velocity-cmd" (*** because I don't know the BBB PRU Hallname). That gives you a working lathe, though it doesn't give you an index, so threading won't work initially. However, this does not mean that threading can't work. It should be possible to configure a synthetic index in HAL. But I suggest you talk to the Machinekit folks about that. ( www.machinekit.io ) As for the Probotix cape not having a PWM output, you can use a step-dir output. PWM is just another aspect of the PRU driver. If you want to convert that PWM to analogue voltage then some external components might be needed, but this can be as simple as a resistor and capacitor. Or, off the shelf, http://store.mesanet.com/index.php?route=product/product&path=74_78&product_id=205 -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
