Dynomotion

Group: DynoMotion Message: 11103 From: wgripp Date: 2/17/2015
Subject: Difference between KMotionCNC and Mach3: slave axis limits
Hello,

I've just completed my second CL Step router with dual, slaved, Y axis stepper motors. This machine is driven by Mach3 instead of KMotionCNC.

I've set up one Lim- switch for each of the Y axes, selecting the Kill Drive limit option.

I've observed that, at least while jogging (I didn't try running a Gcode), if the slaved axis hits the Lim- the whole machine stops when driven by KMotionCNC. But when using Mach3 will only stop the slaved axis, while the master axis will keep going instead. Mach3 plugin is version 4.33k.

At this point I have set the slave axis to watch the same Lim- of the master axis.

I'm asking if this is the intended behaviour, am I missing something ?

Thank you for your help
Group: DynoMotion Message: 11105 From: Tom Kerekes Date: 2/17/2015
Subject: Re: Difference between KMotionCNC and Mach3: slave axis limits
Hi,

I can't think of why there would be a difference between KMotionCNC and Mach3.  When a Slaved Axis becomes disabled as the result of a Limit Switch KFLOP doesn't currently disable the Master Axis and vice versa.  Maybe it should but it isn't 100% clear that that would always be the desired behavior.  When the Master Axis is disabled it can no longer move so it isn't a big issue that the Slave remains enabled.  But when only the Slave is disabled and the Master remains enabled, and continues to move, that would be a problem in most cases.

You might add a watchdog test to disable the other if one becomes disabled with:

    for (;;)
    {
        WaitNextTimeSlice();
        if (ch0->Enable && !ch1->Enable) DisableAxis(0);
        if (ch1->Enable && !ch0->Enable) DisableAxis(1);
    }

Would that solve the issue?

Regards
TK

Group: DynoMotion Message: 11115 From: wgripp Date: 2/19/2015
Subject: Re: Difference between KMotionCNC and Mach3: slave axis limits
Hi Tom,
That would surely fix it !
I'll be able to do some more tests next week .

Thank you again