Not able to control a digital servo

Using Arduino Project Guidance
1

Hello all, I am great at using analog servos and used to "servo.write(160);" but with digital servos it seems that I am unable to control them using that line of code for some odd reason. How do you control digital servos using the Servo.h library?

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I always thought the Servo library was ok with digital servos, and pretty sure I've seen here in the forum that that's the case.

Maybe give the model number in case yours is different from others in some way?

But what do you mean "it seems that I am unable to control them"? Could it possibly be that the digital servo you're using doesn't have enough power compared to the analog ones you have used (maybe it's a very big one?.... you didn't say the model) and it's a power issue not that it's coincidentally digital?

3

kenwood120s:
I always thought the Servo library was ok with digital servos, and pretty sure I've seen here in the forum that that's the case.

Maybe give the model number in case yours is different from others in some way?

But what do you mean "it seems that I am unable to control them"? Could it possibly be that the digital servo you're using doesn't have enough power compared to the analog ones you have used (maybe it's a very big one?.... you didn't say the model) and it's a power issue not that it's coincidentally digital?

I don't believe so, my power supply works fine, it is 6v 1.2 amps. The model is a Sunfounder 55g Servo

4

MrC0829:
I don't believe so, my power supply works fine, it is 6v 1.2 amps. The model is a Sunfounder 55g Servo

How do you know 1.2A is enough?

Forum wisdom is to budget 1A for a standard servo- yours is much higher torque and so possibly needs more than the current you have available.

By contrast then, what model analog servos have you run successfully- let's compare their torques.

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The datasheet says 1.8A Stall Current.

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westfw:
The datasheet says 1.8A Stall Current.

Your Google skills are better than mine-I can't find a datasheet. URL?

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Referenced via their wiki: http://wiki.sunfounder.cc/index.php?title=55g_Metal_Gear_Servo

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westfw:
Referenced via their wiki: 55g Metal Gear Servo - Wiki

Thanks- not often the current even gets a mention, good of them to do that.

Certainly likely to be (at least part of) OP's problem.

9

Hi,
I doesn't matter if you have a digital or non-digital servo, they both respond to the same servo signal.

Have you tried measuring your power supply to the servo, using DMM, while to try to operate it?

Tom.. :slight_smile: