The reality is that a modern dual core mini itx PC board has plenty of power to drive a 3+ axis cnc machine while displaying a GUI in high res.
I've done it, it works, no issues. So I don't think there is a speed problem at all regarding PC horsepower. I think there used to be one when we were dealing with 400 mhz single core X86 CPUs, but not with 1.8 ghz dual cores. Adding a lot of intelligent hardware to offload the PC tasks is simply not needed with LinuxCNC. It is not that we don't want to do it, it is not necessary at all, and probably undesirable. If you do the isol_cpu thing in grub with LinuxCNC it sticks all of your realtime tasks onto one core of a dual core cpu board. So you have almost two computers in one anyway. LinuxCNC does not suffer from the lack of a realtime OS as does Mach3/4. Getting repeatable millisecond response times out of the PC is not difficult with LinuxCNC. The number one problem with Mach3 is that it runs on Windows without the benefits of a RTOS. Because of that it currently has to utilize Arts LPT port stepper driver or offload ANY time critical processing to another CPU on an intelligent card via buffering ( like the Smoothstepper ). The Ethernet smoothstepper at $189 is not cheap. Especially when you add up the entire package: PC + Window$ + Mach3/4 + Smoothstepper + I/O break out for SS. You will eat up more than half a Kilo-buck on hardware and software before you have anything put together. Then you are stuck with whatever bugs the intelligent card developer left you with. Add up the costs for the Dynomotion cardset and you will tear up a $500 bill just on Dynomotion hardware "before" you fire up your C compiler so you can use it with Mach3. 8-O That seems like an extreme effort just to avoid Linux. I have two Raspberry Pis now and they are slick little devices that consume very little power. I have one setup as a LAMP server with a full Apache install and it works. Not exactly a speed demon but it serves up web pages pretty quickly. I can control the I/O pins via a web page with some embedded PHP code. Next up is some python apps to actually make it control something.. I think it will make a good dirt cheap controller for remotely monitored applications via the web, or wifi or cell modem. That said I don't think it would make a good general purpose CNC controller unless it was greatly expanded with other hardware, and even then it would be very limited. Dave On 10/9/2012 1:27 PM, Ron Ginger wrote: > On 10/9/2012 9:02 AM, [email protected] wrote: > >>> Why are some people so hung up on the idea that one box (even a box full >>> >>>> of micros) must be used as the machine control? >>>> >> That is what EMC was conceived as. The whole underlying idea was to >> use cheap, off the shelf, PC hardware for machine control, rather than >> use expensive dedicated hardware. >> >> > Might have been more true in 199? when EMC was started, not so true > today. Micros are almost giveaway items now. > > >>>> With low cost motion devices like smoothstepper, pokeys, >>>> >> A Smoothstepper is considerably more expensive than a cheap PC, and >> can only do one thing. >> As far as I know a Pokeys isn't a real-time motion control device at >> all, but a USB HID device? >> > Pokeys now has a motion control option- it will be shipping for Mach4. > > ron ginger > > > ------------------------------------------------------------------------------ > Don't let slow site performance ruin your business. Deploy New Relic APM > Deploy New Relic app performance management and know exactly > what is happening inside your Ruby, Python, PHP, Java, and .NET app > Try New Relic at no cost today and get our sweet Data Nerd shirt too! > http://p.sf.net/sfu/newrelic-dev2dev > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > > ------------------------------------------------------------------------------ Don't let slow site performance ruin your business. Deploy New Relic APM Deploy New Relic app performance management and know exactly what is happening inside your Ruby, Python, PHP, Java, and .NET app Try New Relic at no cost today and get our sweet Data Nerd shirt too! http://p.sf.net/sfu/newrelic-dev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
