On Wednesday 03 May 2017 21:41:34 Jon Elson wrote: > On 05/03/2017 02:22 PM, Gene Heskett wrote: > > Greetings; > > > > What x86 board, suitably small but not that outpriced yudoo thingy, > > will run linuxcnc well AND can do the spi thing? > > > > Cheers, Gene Heskett > > Well, the various versions of the Beagle Bone run the > Machinekit fork of LinuxCNC fairly well. > The Bone has a lot more I/O available, including hardware > SPI interfaces. > > I don't know any X86 boards that have built-in SPI available > externally. > > Jon > 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. I don't begrudge the guys trying to make enough to buy their beer, but a 7i90 for a bit over $60, simply blows most of the capes I've looked up into the next drainage.
The spi bus out of the pi runs at 32 megabaud, sending 4 byte packets 4 bytes at a time with an extra stop bit between 8 bit bytes. Thats the equ of a 32bit word at 4 megahertz. The parport would have to run at 8 megabytes/second to match that amount of data in that same amount of time. I think... At any rate, that's an order of magnitude faster than the parport can legally do it, it just does not have the ability to deliver the slew rates down the cable that would need. 10% of whats needed is all that is legally available Does linuxcnc have the ability to work over that slow a com channel? Seems like that would be pushing our luck. > ---------------------------------------------------------------------- >-------- 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 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 Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
