Chalker

Yes, those are very good, I have used them quite a few times.  I like that they have a mechanical button to press, not just a membrane switch with a rubber cover. another that I like is the IFM unit https://www.ifm.com/us/en/product/O5K500 Its good if you don't need to train often, since it has the rubber button that can get damaged

So tried out just using the CR input, that worked pretty well. The TSTP worked well also.  However a new wrinkle is that they have decided they want to run paper that has other 'artwork' between the registration marks, with a small clear field just before/after each registration mark, not just plain white or solid colors with a black registration mark.   This makes using the registration mark as the CR input not feasible, the sensor sees to many printed items.  I would need to 'skip over' or ignore the artwork until near the next registration mark.   I believe your earlier suggestion of using MSD and interrupt positioning would do this for me.  If the feed length data was pulled from the point table , and I used that for the length of travel for the interrupt positioning , so that the move would get me to the next "clear" area just before the next registration mark, then have the next registration mark be used as the final stopping point.   I would need to do some programming to step thru each of the conditions and moves, but maybe this is feasible?    Below is a simplified idea of what the paper looks like that is being used.  

Agreed, it would be a very hard stop.  As you suggested, we did it at the end of a deceleration ramp. We would set the feed length slightly longer than the anticipated distance between marks, so the CR would happen very close to the end of decel.   I will have a look at TSTP, and see the interrupt section also.  Thanks!

Thank you glavanov, the Roll Feed mode or Cam function look very promising.  It is a very simple machine that is die cutting paper, and i was hoping to not have to add a Motion PLC to  the panel if the drive could handle the job alone.   We have experimented with using a point table that is 'over ruled' by a sensor input on the CR input, it works, but is kind of heavy handed.

Hello, just starting out with Mitsubishi, hope this question is in the correct forum.  We have a machine with a MR-J4-500A-RJ servo amplifier running in Point Table mode.  The Point Table data for Accel, Decel, RPM and Feed Length is entered via touch screen.  is it possible for this drive to update its Point Table data using a external sensor?   The drive feeds paper between nip rollers for the entered feed length, but we also have some paper with printed registration marks.  I would like to update the feed length to match the marks.  There is a small repeated variation between marks due to the printing process used.  Maybe there is a better way to do this?  open to any suggestions, Thanks!