On Sat, 2008-06-07 at 13:24 -0500, Jon Elson wrote: > Jeff Epler wrote: > > When you set pluto-servo.pwm.#.pwmdir TRUE, the output should be what you > > call "sign-magnitude": > > value after scale+offset PWM Dir > > 0.0 0% FALSE > > 0.5 50% FALSE > > 1.0 100%* FALSE > > -0.5 50% TRUE > > -1.0 100%* TRUE > > > > * may be reduced by max-dc paramter > > > > In emc2 versions 2.2.0 through 2.2.3 there was a bug in the pluto > > drover's pwmdir mode that rendered it completely broken. It should be > > fixed in 2.2.4 and newer. > > > > When in the default mode (pwmdir FALSE), the output is: > > value after scale+offset Up Down > > 0.0 0% 0% > > 0.5 50% 0% > > 1.0 100%* 0% > > -0.5 0% 50% > > -1.0 0% 100%* > > > > * may be reduced by max-dc paramter > > > > There is no way to modify the PWM frequency of the pluto without > > recompiling the firmware. > > > WOW, Dr. Eppler, I believe you have a DIAGNOSIS! With a > negative command into the driver, it looks like synchronous > antiphase! Kirk, can you check if the heating problem is only > showing up in one direction? it also ought to have a > non-symmetrical response. 50% command should give 50% velocity > for a + input value, and the minus valuses should go from -100% > speed to +100% speed, with a command input of -0.5 giving zero > speed. > > Jon
I can certainly try, but I am using the latest 2.2.5 which should be fixed. I have pwmdir set true. I measured only logic levels on the dir pin and analog on the PWM pin. The no load forward and reverse RPM through the range (0 to 5500) was within 50 RPM. -- Kirk Wallace (California, USA http://www.wallacecompany.com/machine_shop/ Hardinge HNC/EMC CNC lathe, Bridgeport mill conversion, doing XY now, Zubal lathe conversion pending Craftsman AA 109 restoration Shizuoka ST-N/EMC CNC) ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
