> -----Original Message----- > From: Peter C. Wallace [mailto:[email protected]]
> > Date: Thu, 23 Jan 2020 10:17:44 -0800 > > From: Chris Albertson <[email protected]> > > > > The trouble with the Mesa FPGA design is that it depends on a computer > with > > good real-time performance. It can generate steps but I don't thing you > > can run a position or velocity PID control loop on the FPGA. > > LinuxCNCs design paradigm requires realtime, this is a design decision that is > supported by our Hostmot2 real time firmware. We have other firmware that > implements motion in the FPGA but this is not suited to LinuxCNCs model. > > > You might argue that its an old fashioned model but many high performance > CNC > systems and Robotics controllers use LinuxCNCs model of a capable real time > host > (real OS with file I/O loadable modules, unlimited memory, massive floating > point performance etc etc) Some of these use Linux and others use real time > windows varients often with Ethercat Peripherals. This makes for a powerful > extensible realtime toolkit (like LinuxCNCs HAL) and complex realtime > responsive coordinated motion. Basically for this type of system you still > need a very capable real time controller hub even if the motor controllers > implement torque, velocity, or position loops > > > Peter Wallace > Mesa Electronics And that really sums it up nicely. As long as there are 'PC compatible' machines out there as desktop/tower to embedded boxes the need for an ARM based Machine Tool CNC controller like the ones for 3D printers is tiny. MachineKit for the Beagle is cool but my Xylotex Cape has the limit switch polarities inverted and that can't be changed. It's why I shelved it and changed to a BC Government Surplus VISTA capable PC that currently dual boots WIN-XP and LinuxCNC. And I have a MESA 7i92H for it. MESA fills a need. It's a pity that it doesn't also fill that same need for MACH4. Then an user could choose between OS platforms evaluating both without swapping hardware. I think though, to address the original theme of this thread, the users out there running LinuxCNC on their machines may never visit this or any other forum. They buy from a supplier that has MESA hardware all in a box. Then they put the machine to work and just use it. It's likely the real number of LinuxCNC users is way way larger than one thinks. Might even exceed HAAS systems by an order of magnitude. John _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
