DS402: Remove set_new_home functionality from homing procedure (fixes #246) #250
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acolomb
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This was referenced Aug 2, 2021
The homing() method will try to manipulate the Home Offset (0x607C) parameter by default. That's not the way the parameter is intended to work. After a successful homing procedure, the drive should set the Actual Position (0x6063) to the Home Offset (0x607C) by itself. By default that is zero, so the selected reference switch flank will mark the new zero position. The library's default behavior here is backwards, and can only work with absolute position encoders. The whole point of homing is to find a physical reference and align the logical coordinate system to it. Trying to determine the desired offset from the value which an unreferenced encoder had at the physical reference point actually destroys that logical alignment. The functionality of set_new_home=True is trivial to do from the application, so remove it completely from homing().
acolomb
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The
homing()method will try to manipulate the Home Offset (0x607C) parameter by default. That's not the way the parameter is intended to work. After a successful homing procedure, the drive should set the Actual Position (0x6063) to the Home Offset (0x607C) by itself. By default that is zero, so the selected reference switch flank will mark the new zero position.The library's default behavior here is backwards, and can only work with absolute position encoders. The whole point of homing is to find a physical reference and align the logical coordinate system to it. Trying to determine the desired offset from the value which an unreferenced encoder had at the physical reference point actually destroys that logical alignment.
The functionality of
set_new_home=Trueis trivial to do from the application, so remove it completely fromhoming().