On Tuesday 11 February 2020 08:14:30 Les Newell wrote: > > What I really > > meant was that with a printer, all the critical timing happens in > > the printer. There are no servo-loops on the PC and you don't need > > a real-time OS to print to paper. > > Who cares where the servo loops or trajectory planning are? When the > end user presses a button to move the machine they don't care how it > is implemented. They only care that it works. Running a machine takes > CPU cycles. You can either use the CPU in your PC or an external one. > What difference does it make? > > Think of your printer example. Do you know or care how much processing > is done in the PC? For example the driver may convert your print page > to PostScript and send that to the printer. The printer then renders > that PostScript to an image of the page. Alternatively the driver may > render the print to a bitmap image of the page and send that to the > printer. The only real difference is in where the processing is done. > To the end user the experience is exactly the same. > > Les > Hear! hear!, Les. The analogy somewhat fails for printers when that convert to bit map is proprietary. Thats the printer maker dictating to the customer what platform his printer can be used with. So to the printer maker who wants to sell me his product, there will be drivers for my chosen hardware and the os running it, or there will be no sale. In my house, it really is that simple.
I am about convinced that while my G0704 is running fairly good, its post is NOT square to the table, I should switch the machine driveing it, currently an elderly Dell that idles at 250 watts, out for something that runs on 5 watts, like the rpi4. I just haven't made up my mind as to the interfaceing hardware. Only one thing is a sure bet, it will be running linuxcnc, and will probably use a Mesa interface. And since integrated drives have hit the market at nominally $100/axis, that may be a later conversion. But I'll need to find a formula that I've not looked very hard for, that converts the Newtons of force these are advertised as having, to the oz/in I'm used to, so I can make intelligent drive size purchase choices. x in particular needs more cajones. 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) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
