On Thursday 31 December 2015 12:26:01 Neil Whelchel wrote: > Hello Tom, > It is my own A20 board design. I could not find anything (cheap) that > has open drain drivers that can handle 5 amps, along with protected > inputs and a FPGA. I made the board specific for realtime automation. > > I call the distro LinuxInside. It is built from source. It uses opkg > to distribute files. I use scripts, patches, and programs from many > places, Debian, OpenWRT, Mikrotik, Gentoo, OpenDesktop and others. It > has custom startup and shutdown programs that are application > specific. The instance that I am using for Linuxcnc is using systemd > at the moment, but I may change that. Part of the problem is related > to udev. When a USB device is plugged in, udev receives messages from > the kernel which may cause modules to be inserted. This is highly > likely to cause an interruption of the realtime services. Part of the > plan is to modify udev to watch the state of Linuxcnc and only take > actions when the machine is in "off" state. There are a number of USB > modules that can block things as well, so I will likely only include > very limited USB support for things that are directly required for > Linuxcnc like USB flash drives, buttons, shuttles, and such. -Neil- > > Don't forget that both keyboards and mice are (generally) wireless AND USB these days. In my experience it was storage devices with a USB interface, like USB keys that play hell with the realtime. It seems the filesystem scans them about every 5 seconds, and does it with the IRQ's locked out for 200 milliseconds or more.
> On Wed, Dec 30, 2015 at 10:56 AM, Thomas Gambone II > <[email protected]> > > wrote: > > Neil, > > > > Are you using an off the shelf A20 board, or did you spin your own? > > > > As for your distro, what was your approach? > > > > Did you start from scratch / Linux From Source approach, > > ending up with your development copy being nearly identical to the > > production copy? > > > > OR > > > > Did you start with a light / customizable distro like gentoo, which > > has package management maintained on the dev side. > > Then you copy a subset of the system to create your production > > distro? > > > > Continuing Jepler's work with the Odroid boards or similar to make a > > robust embedded controller appliance with LinuxCNC would be > > excellent to learn. > > > > Thank you, > > -Tom Happy New year everybody! 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> ------------------------------------------------------------------------------ _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
