The only knock I have on beaglebone black is that the manufacturer does not seem to be supportive of its growth and development. Looks like they are going a different direction. We should have seen a version with more RAM by this point or other improvements. The black was released in Apr 2013 and it has been 3.5 years and that is an age for SBC's.
On Wed, Oct 19, 2016 at 2:50 PM, Charles Steinkuehler < char...@steinkuehler.net> wrote: > On 10/19/2016 12:39 PM, dan...@austin.rr.com wrote: > > > > http://www.machinekit.io/ > > > > Anybody familiar with this? Got a friend who wants to put it on a > > BeagleBone Black. LinuxCNC run onboard a Cortex A8 directly and > > the HDMI monitor, keyboard, mouse etc plug straight into that, not > > just acting as a motion controller from a remote PC. > > > > Notable benefit would seem to be that the IO is very low-latency > > without a motion controller card, and the architecture is 100% > > consistent, as opposed the latency lottery that is picking a PC and > > its MB chipset and seeing how it works. > > > > BBB does have 2x 46 pin IO headers. I'm not sure if all pins can > > be assigned arbitrary HW functions, but it sounds like plenty > > anyhow. > > The BeagleBone does make a decent machine control platform, mainly due > to it's dual 200 MHz PRU cores that can be used for 'bit twiddling" > which helps cover the fairly poor (by x86 standards) interrupt latency > and jitter. > > > He asked me about it and all I can do so far is say "hmm". The > > Machinekit website is pretty sparse. > > Machinekit was created mostly to enhance HAL and RTAPI, with one > advantage being wider support of real-time options (thus making it > possible to run on ARM systems like the BeagleBone, or anywhere else > you can get a Xenomai or PREEMPT_RT patched kernel running). This is > why Machinekit is sometimes thought of as the "BeagleBone" version of > LinuxCNC, but that's not really the case. Other Machinekit HAL > additions like ring buffers, triple buffers, instantiable components, > and remote components are useful on any system, including x86. > > While I use many BeagleBones to control various machines exactly the > way you describe (using an HDMI monitor and KB/Mouse connected to the > BBB), it is not nearly the same user experience as running on an x86 > PC. Everything is noticeably slower on the BBB, and graphics > performance is particularly horrid (to the point that the 3D preview > display is essentially unusable). > > If you're willing to work with the limitations of a low-end ARM > platform like the BeagleBone, they have their place, but for larger > machines, I'd recommend x86. > > NOTE: Most of my BeagleBone driven machines would probably be > considered "toys": various 3D printers, an EggBot egg-drawing robot, > a pick-and-place machine (WIP). All small desktop-sized machines > where having a full x86 PC is somewhat overkill. My one larger > machine (a PUMA-style robot arm) has an x86 controller with Mesa > hardware cards which I hope to get running with a combination of > LinuxCNC (for the recent Joints/Axis update) and Machinekit (for the > HAL layer with ring-buffers and remote components). > > -- > Charles Steinkuehler > char...@steinkuehler.net > > > ------------------------------------------------------------ > ------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
