On Wednesday 17 September 2014 10:50:39 p...@wpnet.us did opine And Gene did reply: > The Mesa 7i76 spindle I/O only operates as enable and dir as far as I > know. The notes say the enable output is hard linked with the enable > for the analog output. It all seems to work properly (outside if the > instant reverse issue) when testing in PnCConf's open loop test. > Nothing in LinuxCNC which leads me to believe there is a config issue > somewhere in the HAL/INI. > > Setting the signs of the search and latch velocities just causes the > axis to locate the home switch in the correct direction, incorrectly > set that as zero and then search for the positive home location in > vain as it runs into overtravel. How do I tell it that the home switch > location is not zero, it is actually 18 or whatever?
that is, in the ini file, HOME_OFFSET. > > I'll look at the toolchange reference, thanks. > > > ------Original Mail------ > From: "andy pugh" <bodge...@gmail.com> > To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> Sent: Wed, 17 Sep 2014 15:20:30 > +0100 > Subject: Re: [Emc-users] New to LinuxCNC and PnCConf and need some > help... > > On 17 September 2014 13:59, <p...@wpnet.us> wrote: > > 1. The biggest issue currently - After some fiddling I have the > > Hitachi VFD controlled spindle operating in the PnCConf open loop > > test where I am able to run it forward and reverse at various > > speeds. I have the spindle encoder connected (A and Index only, not > > sure on CPR currently) and in HALscope I can see the A pulses and > > index pulse. I haven't been able to get the spindle to operate in > > LinuxCNC however no matter what I've tried. Another issue I have > > found is that when running in reverse and stopping, LinuxCNC drops > > the direction line before the VFD has completed the decel ramp, > > causing the VFD to slam the lathe into forward for the duration of > > the decel, obviously not a desirable thing. > > I can see why that would happen, but that isn't what I see with my > lathe/vfd so I suspect that it is something to do with the config at > the VFD end. > I think it is best to configure the VFD for "two button" operation > with one terminal for FWD and one for REV. Then when the spindle-fwd > or spindle-rev signals go false then the VFD simply switches off and > ramps down at its internally programmed speed. > It sounds to me like you may have the VFD wired for ON/DIR rather then > FWD/REV. > > I am having trouble reconciling the statement that you can't get the > spindle to work with LinuxCNC with the statement that something funny > happens when LinuxCNC drops the dir line. > > > 2. I've got the axis homing working in the direction it seems to want > > to run, i.e. in the negative direction, however this seems like a > > bad idea on a lathe to me. If I have a part in the spindle and need > > to re-home for some reason, something not unexpected on a stepper > > machine, homing in the negative direction will crash the toolpost > > into my part. It would seem better to home in the positive direction > > and "zero" to the max travel of the axis. I haven't figured out how > > to do this. > > This is a matter of setting the signs of the search and latch > velocities in the INI. My lathe homes in the positive X and negative Z > direction (as homing into the tailstock sounded like a bad plan). > > > 3. The lathe has an 8 position unidirectional stepper driven tool > > turret with a home switch. I currently have the stepper drive wired > > to stepgen 2 (0=Z, 1=X). I was able to configure an A axis so I can > > manually move the torret, but I've not found any docs so far that > > give me much of a starting point to figure out how to configure the > > tool turret properly for automatic changes. > > There are HAL components to control that style of changer here: > http://wiki.linuxcnc.org/cgi-bin/wiki.pl?ContributedComponents#Boxford_ > Lathe_ATC_toolchanger_component > > They may need tweaking for your particular application, but help will > be available with that. 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) Genes Web page <http://geneslinuxbox.net:6309/gene> US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS ------------------------------------------------------------------------------ Want excitement? Manually upgrade your production database. When you want reliability, choose Perforce Perforce version control. Predictably reliable. http://pubads.g.doubleclick.net/gampad/clk?id=157508191&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
