About Digital Servos

Hi all, my name is Ivan and this is my first post on these forums. I'm a total newbie at this so bear with me a little. I have been reading about the advantages of digital servos and how they have better holding torque and such. My question here is regarding the use or the need of a programmer to get the full 180 degree rotation from a digital servo. I used the sweep sketch to move an analog servo between 0 and 180 degrees with no problems. Would this routine work for a digital servo right out of the box or do I need a programmer to make it move the full 180 degrees? Also, I've read that you can program other features of the digital servo with this programmer, like center point or deadband. Could this features be programmed using an arduino board without a programmer or do I absolutly have to buy the programmer if I want the digital servo to have all its features and ranges of motion available?

Thanks for your time,


RAAAWRRRRR I'm a bear. now you go.

you make no mention of which servo you are using and my mindreading skills are just terrible today. bit of a headache.

I use this servo and it has about 270deg out of the box. http://www.servocity.com/html/spg5485a-bm_standard_rotation.html
no programming required.

Lol... Ok. I'm looking at the Hitec HS-5645MG and it says "This servo can be configured to operate 180° by using any of the following servo programmers: Hitec HFP-25, HPP-21, HPP-21+". That's where I'm getting confused. I assume (correct me if I'm wrong), that this is needed for R/C because the signal's pulsewidth is somehow fixed to a certain range or whatever. So, if I'm using an arduino to drive this servo instead of a R/Control, would I still need the programmer or is it enough to just send the appropiate pulsewidth or the angle using the servo library?

I honestly dont know. I'm a noob to servos. I just know mine does over 180 out of the box with no programmer. Looking at the pictures from the link above I thought I was going to have to program it past 90deg but it just worked when i got it. So not really sure. Somebody will probably hop in with an answer soon though.
good luck.

Oh I see. Thank you anyway. I've seen similar posts in other forums but it is never clear if the programmer is really necessary or one can just do the programming stuff directly from the arduino board.

The methods of programming the servos are proprietary. I've seen a few posts where people have attempted to create their own programmers but it doesn't look like it's a novice problem. I think it would be worth your time to just buy the programmer.

Oh ok. Since I'm just starting to learn all this stuff I guess I'll be sticking to analog for a while. I don't particularly need the holding torque and precision of digital quite yet, but its good to know for later projects. Thanks a lot.