End Stops... Series/Parallel microswitch questions

I am finally about to assemble my Prusa V2.

I have a question regarding the endstops...

Currently it looks as though both ends of the X axis are sensed on 1 micro pin, the Y on a second pin, and the Z on a third pin.

I am not sure why 3 pins are used because it seems to me that if an endstop is reached while printing, then the printer must stop because in theory this should not happen. This is presumably why each pair of endstops can be joined.

Now, during setup, it should be quite simple to step the printer to each endstop and set it up internally in the micro.

So, we could indeed simplify the whole process by just using 1 input or 2 inputs to the micro. Here is what I mean...

All 6 endstops could be parallelled into 1 sense line on the micro (for N.O. microswitches) or all series (for N.C. microswitches). Alternately, using 2 micro inputs, one end for each of X, Y & Z could be parallelled/series and the other end for the second wire.

Is this feasible and does it make sense? or is there a reason for the current way(s) it is done?

BTW would this be better in the electronics thread???

We do not use the endstops during the print. They are disabled in the firmware during the print to avoid false triggers. Also I have never seen anyone wire the min and max to the same pin. Most electronics have pins for both min and max if wanted but most people only run one or the other as they are for homing and nothing else. We are not short on pins either with most of the current electronics so I see no reason why we would need to combine the endstops into one circuit.

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Sublime: Thanks. I didn't realise only one end had endstops, but that makes sense.

If you wire them in parallel they are ambiguous if they are triggered at start up. You would have to manually ensure none of the axes where at the end

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