Re: [CAD_CAM_EDM_DRO] servo2go Model-II card and anyother software than EMC

Leslie Watts wrote:

>One aggrevating bug occurs when the the stg wakes up with seemingly
>random numbers for axis positions. If the home switch is on one end
>a large number may indicate a position beyond it...in that case
>emc will home the other way.
>
>Usually powering down the computer fully for a while will cure this,
>but we really ought to initialize zeros or something in the position
>registers so it never happens.
>
>

It is supposed to. I had some problems with this on the early driver for my
interfaces. If EMC is not able to write zero to the position counter in the
encoder interface, it will usually cause the "bad encoder value" suppression
to make the axes fail to see encoder movement. The displays will stay
at one constant value. The initial axis value comes from the .var file
which holds the offset between home and the last coordinate offsets
that were set.

I think I may have had this problem once on an STG card. I couldn't find
anything wrong with the encoders, but the display didn't move when I
moved the machine. Powering off and rebooting fixed it.

So, EMC is SUPPOSED to write zero to all axes, but it can fail under
some circumstance. But, I don't think that will cause a problem homing,
but more likely an axis runaway.

Jon