I think this discussion belongs on some other newsgroup now.  It is asking how to design a CNC system and that's not what we're here for.

Good luck though.

-- Mark


On Fri, 01 Jun 2001 15:08:46 +0200, Roland <rv@ronetech.com> wrote:
> > I avoid Windows for real-time applications if at all possible, but my main reason is uptime of the OS :>
> 
> sorry, i don't understand "uptime of the OS :>"
> 
> you avoid Windows for real-time applications: did you already made some ?
> 
> > Does the PC control the stepper moters of the CNC machine directly or is there a controller in the CNC already? or do you have an ISA/PCI card sitting in the PC?
> 
> not only stepper motor, cc motor as well.
> 
> the cnc is a software cnc.
> there is an external board based on a CPLD, plugged on the ECP Parallel port.
> It provides only low level services: io, wired security, some wired logic and power management.
> 
> > (not taking into acount development cost of the board and associated software).
> 
> that is the problem, i wonder if it is cheaper than making a Windows device driver. the big if is: can a device driver do the job ?
> 
> And a PC Motherboard is quite a powerfull and cheap board..
> 
> > Yes. However you may find adding an external controller is cheaper then trying to get your windows program to run fast enough.
> 
> that is the question.
> 
> I just know some windows program/device driver use to make software MPEG or MP3 decompression.
> 
> that is real time and quite fast isn't it ?
> 
> In fact, i know there is special PC cnc board: see
> www.galilmc.com, ni.com
> and other.
> 
> But we have some 'virtual cnc' classes i hesitate to trow away.
> 
> I'm just exploring all the possibilities. I try to evaluate what Windows can do before taking a decision.
> 
> Thanks and Regards
> 
> Roland
> 
>