Quote Originally Posted by AbuMaia View Post
Roxy, that comment block explaining the different arguments passed to G29, the one for E is not clear to me. If one uses E, what should they expect to see? From what I've seen in your Probe Repeatability test, E caused the servo to lift the probe each time. In this comment block, though, it sounds like it's used to keep the probe extended for the duration of probing.
So I can't speak definitely! I haven't run this code yet. I'm going to have to port it back to my machine. But the Enhanced G29 is supposed to leave the probe down while taking all the points by default. Specifying the E option should make it go back to the original behavior and 'E'ngage the probe and un-'E'ngage the probe for each point.

The comment says:

Code:
                Controls engagement and retraction of the Z-Probe.  It Defaults to leaving the
                probe engaged during the probing of the n x n grid.
So specifying the 'E' would Control engagement and retraction of the Z-Probe.

With nothing specified, the default behavior is to leave the probe engaged.

Please feel free to help make the documentation clearer! For sure people writing code make assumptions about what is obvious and what is not obvious. And if you do make the comments better... Maybe you can make the Left, Right, Front, Back comments better! The big problem with that is it assumes the origin for the person's bed is at the left front. That is not always the case. (I'm exactly opposite to that because of early flaws in the G29 code where it could not take negative offsets) But what can be done (either by switching the option names or by a different explanation) to make that better?