Reset "Encoder Index found" status flag

[ImBatman]

I am using LabWindows/CVI 2012 to interface with the PCI-7333 motion controller card. I need to change the home position occasionally and am using the flex_find_index function and then using an offset to accomplish this. The problem is after the first execution of the find index index command the Encoder Index found status bit stays on and when I execute the find index command again it immediately stops. How do I clear this status bit?  I saw another discussion about this in this forum where the find index should clear this bit when it runs but this isn't happening for me. 

[KathrynTheGreat]

Hello Mr. Wayne,

Although most of my NI-Motion programming experience has been in LabVIEW rather than LabWindows/CVI, I’ve spent some time looking into your issue today and have a few clarifying questions for you. I’m working from the section on page 9-7 of this manual that goes into depth on the find_index function, and from what I’ve seen, it looks like you’re using the function properly.

What kind of code are you running after finding the encoder index the first time? Does the motor move at all, or is it still at the correct index when you restart the program? It’s possible that this flag will remain set until the motor moves off the index. There may also be a clear flag command that you need to run, but I haven’t seen anything along those lines so far.

Are you sending the function a non-zero offset value?

[ImBatman]

Hello Kathyrn,

Thanks for the reply and also liked the Mr. Wayne reference. I finally figured out what was happening. When the find_index function started I would see the encode index found flag go off but then turn back on after 80 steps. I made sure I tried this at different locations to ensure that I wasn't on the index. That seemed to tell me that the find index function was working so decided to check the settings in NI-MAX. Switched the polarity from low to high and everything worked. Seems like it is always the simple fixes that cause the most problems.

[KathrynTheGreat]

Haha, isn't that the truth? I'm glad you found a solution, and that you posted details in case anyone runs into similar issues in the future. Thanks for being the hero LabVIEW deserves.