Hi Jon I have it feeding back slowly to latch the proximity switch, but it's picking up from an encoder pulse that it found 6 inches away from the home position unless I move the machine close to the switch, close Linuxcnc, reload LinuxCNC and command a zero return from there.
I disconnected the proximity sensors last night because I got fed up, but it wouldn't take long to reattach them and make a video of what I'm experiencing. To recap, here is where I'm at, maybe you can see the error in my config: " here's my current setup: 7i76e input 4 -> X mechanical switch 7i76e input 30 -> X proximity sensor 7i76e input 5 -> Z mechanical switch 7i76e input 31 -> Z proximity sensor INI file set up for home_use_index = yes hal file additions: loadrt encoder addf encoder.capture-position servo-thread addf encoder.update-counters servo-thread net x-home-prox hm2_7i76e.0.7i76.0.0.input-30 encoder.0.phase-Z net x-home-index-enables joint.0.index-enable encoder.0.index-enable net z-home-prox hm2_7i76e.0.7i76.0.0.input-31 encoder.1.phase-Z net z-home-index-enables joint.1.index-enable encoder.1.index-enable I got it to work with this setup, but it seems like LCNC is catching the first index pulse it sees, touching the mechanical switches, fine feeding until it finds the prox pulse but then rapids back to the very first pulse it found, which doesn't make any sense to me. If I manually jog the machine close to where the home switches are, restart LCNC then initialize a home sequence, it'll do what I expect it to do, but if it's (as an example) 100mm from the home switch, it will search for the switch, touch, back away, fine feed until it finds the closest proximity pulse, then rapid back 100mm, so it's not very robust at this point. " Phil T. The Feral Engineer Check out my LinuxCNC tutorials, machine builds and other antics at www.youtube.com/c/theferalengineer On Mon, Mar 1, 2021, 2:14 PM Jon Elson <el...@pico-systems.com> wrote: > On 03/01/2021 11:02 AM, Feral Engineer wrote: > > Hi Jon > > > > No encoders. Besides the 7i76e and raspberry pi, the machine is using the > > original steppers and electronics. > OK, without encoders, then you are limited by the servo > period. So, figure some way to tie > the sensor in with the mechanical switch, and make the home > move slow enough so you are doing less than 1000 > steps/second. Previous messages mentioned some schemes to > tie the sensor in with the switch. The idea is that > LinuxCNC will make a fast approach until the and of the > sensor and switch show true at HOME_SEARCH_VEL, then back > off and approach slowly until they show true again at > HOME_LATCH_VEL, and that is the home position. > > Jon > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
