On Saturday 04 July 2015 06:43:27 John Thornton wrote: > Is your index pulse the correct polarity? > > http://gnipsel.com/linuxcnc/tuning/encoder.html > > JT
I haven't previously seen that, John, thanks. ISTR the index pulse detection is on an edge, so the only effect of changing its polarity should be the equ of its width on the lockup condition, perhaps 2 degrees maximum, dependent on how wide the index slot is in your machine. The slot opto's I used on the lathe, have active cmos outputs, driving to within a few millivolts of which ever rail they are at. Dead square waves, with 20 nanosecond or less rise & fall times. The ones I have partially constructed for the mill are straight phototransistor, which I will consider as OC outputs. The one specification chart I was able to find says they need 50 to 60 of excitation current, so the first approximation, running on 5 volts, will have 100 ohm current limiters, for the leds which should give around 40 ma, and it says the detector has a 24 volt breakdown and 30 ma current. Wired as open collector, with a 4.7k pullup to help speed up the shut off, it ought to work. With OC circuitry, a pullup seems like it will be needed. OTOH, with the opto's in the bob usually being capable of working either way as long as the applied polarity matches the wireing, then we are looking at the current pulse they get as the index slot goes by. Looking at it with a voltage measureing device such as a scope needs an eye trained to use the area of the on pulse that is nearly flat on the bottom, and mentally convert that to the actual pulse width measurement. The rise times after, if there is not a separate pullup, aren't really a factor. The fact that its rising means the current has in fact stopped. So we need to think in terms of the current thru the LED in the opto devices. And this is why you really really need a pullup in order to assure that noise pickup in the cabling isn't miss-interpreted as a false, 10 ns wide, index pulse. The opto's in the BoB, being fairly low impedance devices, can probably tolerate quite a bit of picked up noise, but the presense of a pullup resistor will increase that noise margin, a lot. You (Tom E. I believe it was) are looking at it with the halscope, and if you can see it propagating out of the BoB and into LCNC's logic where the halscope can see it, then it is working and I'd say the problem is someplace else. Why it switches to g17 needs to be found. G17, IIRC is XY, not XZ. That is the real error. In single step mode, you may have to hit step twice at the wait for index point in the cycle, but as G76 is canned I am not sure you would have to hit the step button again. The one time I tried it, years ago, ISTR it ran the cycle to completion once past that original wait for index. But that memory is now 2+ years faded so I won't swear it. I believe the next thing I might do is printout that bit of the codethe code, and exec it step by step using the MDI interface. With an empty toolpost of course... > On 7/3/2015 7:34 PM, Tom Easterday wrote: > > Thanks Gene. I do have an index pulse on the encoder, I can see it > > in hal scope (on hm2_5i25.0.encoder.00.input-index) when i run the > > spindle. In my hal config I have: > > net spindle-index-enable hm2_5i25.0.encoder.00.index-enable > > motion.spindle-index-enable net spindle-index > > hm2_5i25.0.encoder.00.input-index > > > > Again, it is weird that G17 pops up and it stops, isn’t it? I > > should also add that it runs fine in the lathe.ini sim. Not sure > > what is going on… -Tom > > > >> On Jul 3, 2015, at 8:21 PM, Gene Heskett <[email protected]> wrote: > >> > >> On Friday 03 July 2015 20:15:51 Tom Easterday wrote: > >>> I am trying to do threading on a lathe using the NGCGUI g76.ngc > >>> routine. Other operations, facing, turning are working in NGCGUI. > >>> When I get to the G76 line in the code (was stepping through it in > >>> Axis) it just stops and sits there. The only reason I can see for > >>> it stopping is that my plane changes to G17 (from G18 which is set > >>> in the g76.ngc routine) for no apparent reason. The spindle > >>> turns, but there is no further movement. I believe I have correct > >>> values for every G76 parameter and everything else is fine. I > >>> have no explanation for why the plane changes to G17 - there is no > >>> such command in the .ngc file. I see in the release notes for the > >>> various 2.7.X releases that in 2.7.0~pre5 this was done: fix > >>> velocity & acceleration values on non-G17 arcs > >>> I wonder if this could have messed something up, or if there is > >>> some other bug in 2.7.0~pre6. Any ideas? > >>> > >>> -Tom > >> > >> Verify, with a scope, that you have a valid index pulse Tom. If > >> its missing, it will sit there forever as that is its start this > >> stroke signal. > >> > >>> ------------------------------------------------------------------ > >>>---- -------- Don't Limit Your Business. Reach for the Cloud. > >>> GigeNET's Cloud Solutions provide you with the tools and support > >>> that you need to offload your IT needs and focus on growing your > >>> business. Configured For All Businesses. Start Your Cloud Today. > >>> https://www.gigenetcloud.com/ <https://www.gigenetcloud.com/> > >>> _______________________________________________ > >>> Emc-developers mailing list > >>> [email protected] > >>> <mailto:[email protected]> > >>> https://lists.sourceforge.net/lists/listinfo/emc-developers > >>> <https://lists.sourceforge.net/lists/listinfo/emc-developers> > >> > >> 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 > >> <http://geneslinuxbox.net:6309/gene>> > >> > >> ------------------------------------------------------------------- > >>----------- Don't Limit Your Business. Reach for the Cloud. > >> GigeNET's Cloud Solutions provide you with the tools and support > >> that you need to offload your IT needs and focus on growing your > >> business. Configured For All Businesses. Start Your Cloud Today. > >> https://www.gigenetcloud.com/ <https://www.gigenetcloud.com/> > >> _______________________________________________ > >> Emc-developers mailing list > >> [email protected] > >> <mailto:[email protected]> > >> https://lists.sourceforge.net/lists/listinfo/emc-developers > >> <https://lists.sourceforge.net/lists/listinfo/emc-developers> > > > > -------------------------------------------------------------------- > >---------- Don't Limit Your Business. Reach for the Cloud. > > GigeNET's Cloud Solutions provide you with the tools and support > > that you need to offload your IT needs and focus on growing your > > business. Configured For All Businesses. Start Your Cloud Today. > > https://www.gigenetcloud.com/ > > _______________________________________________ > > Emc-developers mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-developers > > ---------------------------------------------------------------------- >-------- Don't Limit Your Business. Reach for the Cloud. > GigeNET's Cloud Solutions provide you with the tools and support that > you need to offload your IT needs and focus on growing your business. > Configured For All Businesses. Start Your Cloud Today. > https://www.gigenetcloud.com/ > _______________________________________________ > Emc-developers mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-developers 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> ------------------------------------------------------------------------------ Don't Limit Your Business. Reach for the Cloud. GigeNET's Cloud Solutions provide you with the tools and support that you need to offload your IT needs and focus on growing your business. Configured For All Businesses. Start Your Cloud Today. https://www.gigenetcloud.com/ _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
