On 11/12/2016 08:29 PM, Gene Heskett wrote: > Back again; > > I stuck the 2nd one back in, right way to, but I guess it did not survive > the reversed polarity, it can only pull down about half a milliamp. I > have 7 more of them so I will use new ones for the last 2, A/B. > > But watching the one in the index position, I note that they stay in the > last state, but does that affect the index adversely? > > Yes, they have a flip-flop that is driven by a comparator that checks the difference between the two sensors in each unit. So, they DO latch, that is the behavior as per the data sheet.
Now, with LinuxCNC, all you need is consistent operation in ONE direction only. For instance, in a rigid tapping operation, the spindle encoder is synched to the index at the beginning of the operation and then the encoder is allowed to count up and down as the tap progresses in and then backs out. The spindle encoder is NOT resynched during the whole operation. It is pretty clear that the index pulse would pick up the opposite side of the hole or notch when running the opposite direction, but that should not be a problem as mentioned above. It also seems that the A-B quadrature might slip one quadrature count when the spindle reverses, but would then slip the other way when reversing again. And, I'm not sure that would actually occur, either. Anyway, a tiny slip in the spindle count should not be much of a problem in most cases. I've rigid tapped thousands of 4-40 holes with combo drill-taps without any problem, using the ATS667 sensors. Jon ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today. http://sdm.link/xeonphi _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
