Question about a component connected to the step size selection pins on Melzi board

What's the 'component' connecting MS1 and MS2 on the stepper drivers?

http://reprap.org/mediawiki/images/7/7d/Melzi-circuit.png

Looking at the physical board, it just looks like two copper pads, connected to each other.

From the spec sheet, this appears to just be to select the step size.

They are pairs of pads shorted by solder blobs. To change the selection you either add the blob or leave it off. The ones I supply have them all shorted for x 16.

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[www.hydraraptor.blogspot.com]

Ah that makes sense - cheap way to do it I guess!

Yes, and there is not really any need to change from x 16 unless you need a step rate faster than the firmware can manage.

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[www.hydraraptor.blogspot.com]

Just an FYI, even if you wanted to change the multiplier, the driver can be speed pulsed, to the next several steps, and will settle and the new step as long as it is less than a whole step. This method in theory could be used in software to overcome some speed limitations in firmware.

So if you need to move 4 increments, then you could pulse those 4 step pulses all together with a 2-5us delay a pulse. Not smooth and not great for acceleration, but manageable. This only works if no optical isolation is used and capacitance is low on the trace to the driver IC.

This is a way to control multiplier in software, rather than having pins to the chipset, or manually adjusting the pins.

Perhaps someone may find this information useful, for controlling z axis perhaps in helical motion?