On Thursday 04 May 2017 13:14:07 Jon Elson wrote: > On 05/03/2017 11:36 PM, Gene Heskett wrote: > > On Wednesday 03 May 2017 23:44:02 Jon Elson wrote: > >> On 05/03/2017 09:28 PM, Gene Heskett wrote: > >>> The killer in the beaglebone soup is the cost of the "capes". > >>> You've over $200 plus psu's etc before it can turn 2 motors at the > >>> same time. > >> > >> Umm, the CRAMPS board is $79.95, and I sell the 8825 drivers > >> for $5 each, but I get them from China for about $1.30 > >> each. > > > > The 8825 does what? I need to take another look at your site I > > guess. > > 2 A 35 V stepper driver.
Whereas I'm at 43 volts and 5 amps on x(8 wire motor in parallel), 65V and around 3.5A on z. And fixing to add another 20 volts to x, its tapped out at about 40 ipm. Fairly small fine threaded ball screw. > >> The BeagleBone is $55, > > > > And how many cores & how fast is its arm? > > I think it is only one core, 1 GHz. Works fine for > Machinekit/LinuxCNC control of Cartesian machine, but ssh -X > connection from a machine with a screen is noticeably slower > than an X86 PC with directly-connected screen. Where this pi has 4 cores, 64 bit, and is running at 1.2GHz And twice the memory. Needs more yet. So I think I'll stick with it unless this last experiment fails. dd is still munching away at creating a clone of the only u-sd that will still boot it. Then 2 boxes of deck stuff just walked up and plopped themselves down on the front deck, which I am suspecting I'll need to modify the gazebo as its too tall to fit under the roof overhang. Might wind up ripping out some greenery and extending the deck, outward by a foot or so and east 5 feet as it will block the front door otherwise. Fun and games with 2x8's for framing and 2x4's for flooring. If it ever happens. Dee said no. So I've spent the afternoon assembling the deck furniture, which came in flatish pieces. Got the corner chair piece and 2 chairs, but still have 2 in the box when it started a light rain, and my back said enough already. So dinner is warming in the microwave. > > The Beagle Bone has 2 PRU processors (200 MHz real time > 32-bit CPUs) that Charles Steinkuehler set up the framework > for so that LinuxCNC can do fast stepping, PWM and encoder > counting. Not quite FPGA performance, but WAY faster than > software stepping. So, that relieves the ARM CPU from the > base thread tasks. > > Jon > Thanks Jon. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ 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 [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
