> I played with those values, setting stepgen.maxvel and maxaccel to 0 > like the doc says in order to not limit it. Not much improvement. Then I > tried to increase vastly the MIN_FERROR, and that allows to go through > but I get some occasional grinding noise (missed steps I think) when > doing a test (back and forth on one axis) >
> One thing I noticed is that the .hal file written by pncconf does not > specify the servo_base_period on the EMCMOT line. > It's specified in the INI file - the HALfile looks it up there. > What is infuriating is that within pncconf, I can test one axis with > fast movement back and forth and it is real nice, smooth, no missed steps... > > Is there a way to find out which exact parameters pncconf is using when > it launches the tuning applet ? Well it should use the parameters shown in the test. If you close the test with cancel it won't copy those parameters to the axis page. But to answer your actual question: yes there should be a halmeter showing and you can look up the pins that specify acceleration, velocity and drive timing. here is a list of the relevent pinnames: http://www.linuxcnc.org/docs/2.5/html/drivers/hostmot2.html#_pins_3 or you can open a terminal and while the test is running type: halcmd show by the way what version of linuxcnc are you using? > > On 2/9/14 5:25 PM, bruno wrote: > > > > This is a stepper system, trivkins, 3 axis mill. > > I kind of assumed that the tuning in pncconf is using the > > configuration that it will write, it's not very useful if one tunes > > things but then the parameters to use are different... > > > > so you are referring to these > > > > * > > > > /STEPGEN_MAXACCEL = 21.0/- Acceleration limit for the step > > generator. This should be 1% to 10% larger than the axis > > MAX_ACCELERATION. This value improves the tuning of stepgen's > > "position loop". If you have added backlash compensation to an > > axis then this should be 1.5 to 2 times greater than MAX_ACCELERATION. > > > > * > > > > /STEPGEN_MAXVEL = 1.4/- Older configuration files have a velocity > > limit for the step generator as well. If specified, it should also > > be 1% to 10% larger than the axis MAX_VELOCITY. Subsequent testing > > has shown that use of STEPGEN_MAXVEL does not improve the tuning > > of stepgen's position loop. > > > > looking at the hostmot driver > > > > * > > > > /maxaccel/- (Float, RW) Maximum acceleration, in position units > > per second per second. If set to 0, the driver will not limit its > > acceleration. > > > > * > > > > /maxvel/- (Float, RW) Maximum speed, in position units per second. > > If set to 0, the driver will choose the maximum velocity based on > > the values of steplen and stepspace (at the time that maxvel was > > set to 0). > > > > seems like it would be best to specify 0 for both of those as the per > > axis limits would still be in place ? > > I am going to play with that and see... thanks for the reply > > > > On 2/9/14 4:04 PM, emc-users-requ...@lists.sourceforge.net wrote: > >> Date: Sun, 9 Feb 2014 15:03:40 +0000 > >> From: andy pugh<bodge...@gmail.com> > >> Subject: Re: [Emc-users] mesa 5i25, pncconf working but not linuxcnc > >> To: "Enhanced Machine Controller (EMC)" > >> <emc-users@lists.sourceforge.net> > >> Message-ID: > >> <CAN1+YZV2iQb-AQmWE4TYbxithWSFmSvuMRP-kxk8=jhwpjd...@mail.gmail.com> > >> Content-Type: text/plain; charset=ISO-8859-1 > >> > >> On 9 February 2014 11:30, bruno<br...@tinkerbox.org> wrote: > >> > >>> >After configuring, I started linuxcnc (with tklinuxcnc as I have opengl > >>> >issues with axis right now), and it immediately gives me joint following > >>> >errors. No move, nothing. > >> It might be that Pncconf doesn't teack following error, or has higher > >> limits. > >> > >> However, if this is a stepper system then "following error" means > >> something slightly different to what it means in a servo system. It > >> means that the system has not been able to make the number of steps > >> requested. > >> > >> What this typically means is that the system stepgen accelleration > >> numbers are bigger than the step generator limits. Have a look through > >> your INI file and check that the step-generator accel limits are "a > >> bit" higher than the system and axis limits. > >> > >> Is the machine a gantry system? The other possibility is that the > >> step-generator feedback is going to the wrong axis. > >> > >> -- atp If you can't fix it, you don't own it. > >> http://www.ifixit.com/Manifesto > > > > ------------------------------------------------------------------------------ > Managing the Performance of Cloud-Based Applications > Take advantage of what the Cloud has to offer - Avoid Common Pitfalls. > Read the Whitepaper. > http://pubads.g.doubleclick.net/gampad/clk?id=121051231&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Managing the Performance of Cloud-Based Applications Take advantage of what the Cloud has to offer - Avoid Common Pitfalls. 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