Lynxmotion Tech Support

So i got few HS-5645MG and the angle goes from 20 to 161, if i go any higher than 161 or any lower than 20 it stalls... Any idea on why this is?

Sounds about right... I don't see these servos up in the Lynxmotion store, but there are for example: http://www.lynxmotion.com/p-744-hs-5685 ... servo.aspx

And it states, that:
That is by default the servos ship with their internal program limiting their range to 140 degrees, but you can use one of their digital servo programmers and update the programming to allow them to go 180 degrees.

Kurt

but why not 0 to 140?

Because...

The question is where are you getting these angles from? The servos respond to pulses where a pulse whose range of the pulses center around 1500, which we typically say is at 90 degrees. So the 140 breaks down to 90 +-70.

Now if specifically you are talking about on an Arduino using the servo::write command, you can more or less map it anyway you want... If you fudge around some. That is:
The write method, simply uses the map function to map what was passed in (or defaulted to) min and max values for the servo in the attach method.

Kurt

So for biped functionality is it worth it to buy a servo programmer (like this one: http://www.servocity.com/html/hpp-21_pl ... ammer.html) to get that extra 40 degree?

I don't have any of these servos, so for me no I think you might also get away with http://www.lynxmotion.com/p-615-hmi-ser ... r-kit.aspx
But I am not sure... Have not been there, have not done that...

Kurt