Index homing Heidenhain ls 403/exe602

Hi!
Is it possible to home a machine only using the scales and no other limit switches? Have found a bunch of posts regarding this, but none gave me enough clarity. In one i think Andypugh did some testing/developing to get this to work?

/Hampus 

It should be possible if there is only one index
rather than periodic index marks

My Maho homes off the Heindenhain LS-403 scale index marks. Works the same as homing to a a separate homing switch.

Nice!

I have a MH500w2 i'm working on! I looked through your files and tried messing around abit. But i'm afraid i can't figure out how to add what appears to be different. you have some layer of "home-x" parameters which i seem to skip in my ini (made with Mesa CT). i'll add my files if you have the time for a quick look.

I'm running LCNC 2.10 with Gmoccapy.

RotarySMPs hal/ini files are from LinuxCNC 2.7 or earlier so before the
AXIS/Joint separation change.

Newer hal/ini files like yours put the homing ini constants in "JOINTN"
sections

Ok! I'm really a beginner at this...

My machine homes and the dro goes green on all axis Problem is that it seems to be doing so on some kind of periodic index from the scales, so after homed it has no idea where along the scale it is at the moment... must be missing some important lines in my configs.

If you  scale has periodic index marks you need to coarsely position
the axis before the final home to index (this is usually done with a home switch
but could be done by jogging to a mark and then homing to index)

What about the "rawcounts"? when i quickly had a look at them in halscope they seemed to have "0" at a fixed location, do you think that's something i could use in some way?

Raw counts will be set to 0 when LinuxCNC starts so its still
just a relative count number.

What is the spacing between index marks on your scale?