Jon Elson wrote: > Jack Coats wrote: >> For a different approach... Open source controller hardware with >> attached display. >> <snip> >> >> Another option might be to get one of the 'single board' Linux machines, >> use it to run >> EMC, and do AXIS on a 'display computer'. This might make it easier to >> do the 'port' and still >> keep the 'real EMC2' on hardware without display (or sound). It could >> use either USB or >> Ethernet attachment. >> >> I could even see running Axis (or equivalent) on one of the little palm >> top computers, and EMC on >> an 'attached controller box'. >> >> Yes, there is some hand waving and daydreaming in this, but one day we >> need to start thinking this way. >> > My main question is "Why?" Why throw away years of effort that has > produced a VERY powerful and flexible framework that WORKS?
Exactly. Sending commands to CNC components (motors, sensors, etc.) through USB attached micro controllers is too hard to support with limited resources not to mention basic timing issues. > Is there a real time patch set for that "single board" Linux machine? > Without that, it is worthless for our purposes. Why need TWO computers, > when one works fine? Think of all the debugging and logging hassles > when you don't have hard drives on these computers, which would be the > case on many of the single board embedded systems. > I believe that "embedded CNC computer" is a viable option. It all depends on what we take as embedded. With numerous mini itx boards on the market today it should be possible to find one that's good enough for controlling some CNC machines. CAD design etc. can all be done elsewhere with files transported over the physical or wireless network, or flash memory (USB, SD) to embedded CNC system. It's better not to mess with the CNC system when CAD or some other program needs an upgrade for example. I would not want to have somebody browse the websites while CNC machine was running on the same system so a dedicated computer makes sense. > I certainly don't see the need for a move in this direction, yet. ... yet. And that's the key. Being involved in USB memory devices at work I can say with high confidence that years of classic hard drive for basic computer storage are numbered. Let's face it, it's a mechanical device not very suitable for a shop floor where temperatures and vibrations reach over recommended ones. SSD (Solid State Drives) are going to take over due to lower power, reliability, weight, etc., in few years. Like it or not, USB is going to play a major role in all it's current and future forms in computing environment. Even high end servers are now coming with the OS installed on SD cards for example. I see no reason for EMC not to bootup from SD card and mostly run in memory with only file or possibly video exchange needed over the network. > Maybe, in the future, desktop PCs will be so horribly encrusted with > bluetooth and other wireless "crap", variable CPU speed, battery and > thermal management that they will be forever unable to do anything in While that might become a reality, the future for RT boards looks very promising. Open source is going places including hardware. Take http://beagleboard.org for example. I've seen a demo of that board recently with focus on robotics. >From what I learned, this is very powerful board with a lot of possibilities. It seems that Ubuntu is going to be well presented on that platform which makes me think that it will be suitable for CNC eventually. I'm not advocating this board as "the solution" for CNC as I'm not familiar with it enough, just want to point out that new options are opening as the old ones are fading away. Who needs silly parallel port when real IO ports are desired? Don't we have enough problems with PP in different modes, BIOS setup etc.? Spending much time on PP port for serious RT is not worth it IMO when low cost IO boards are available. > real time. We may have to develop a hardware compatability list of our > own, testing specific models for RT performance, parallel port > compatability, etc. > I can recommend a few models myself, I've been using off-lease Dell > Optiplex boxes with good results. > > > Jon > -- Rafael ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
