Is there a way to tell the machine to go to the home point automatically after setting one? Re-phrased, I want a button that lifts the pen and moves it to the current home point when pressed. I don't see it in the 1.2.4 controller software.

Go!

=ml=

Yes you're right there is no built-in way of doing it. If I wanted to do that normally I would do "move pen to point" and click on the home point on-screen.

What do you use the function for? It's worth keeping if lots of people are going to use it, I think there's a way of submitting patches using SVN, but just drop me an email with the segment in it if that turns out not to be trivial. OTOH, it's a straightforward addition so I can figure it out myself.

"Set pen position" is basically a free-hand "set home". It tells the machine that the gondola is in a particular place. Select it, and then click somewhere on the machine in the controller. I use it mainly for testing, where I want to tell the machine roughly where the gondola is without having to re-home.

sn

Fair enough, I've just added a "return to home" button in the repo - not out in the zips yet. Registration is only a problem if you cut the power (or otherwise recalibrate) between layers and this won't help with that - "return to home" can only ever move back to where the machine thinks the home is, there's no guarantee that it's physically the same position as it started.

I think it could be useful though if there was a kind of "holder" at the home position that the gondola will latch into at the beginning and end of each session. It's a kind of alternative to self-calibration I suppose.

Yes having the files in trunk rather than in trunk/polargraphcontroller was an early mistake that constantly irritates me - maybe that'll be the first fix for 2013 🙂

I always thought that the limit switches would be on the surface, somewhere near the motors, but I do quite like the idea of having a latching dock of some sort as the home point. It wouldn't solve the problem of the initial calibration, unless the gondola was already in the dock on startup. So I don't know if it'd be worth it.

And there are four pins broken out on the polarshield that are there for that purpose - a x min and max and a y min and max. They are digital inputs and there's a +v and gnd next to each one.

The 0.5 is because the float always usually gets truncated down, so even 1.9 still gets issued as 1 when converted to an int. Adding the 0.5 means that it gets converted to 2 instead. I kinda thought this was a good idea at the time, but I'm not really convinced about whether it makes things better (more accurate, or true) or worse.

Happy new year!
Sn