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Author Topic: SERVO ISSUE [UNO]  (Read 1307 times)
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Hey there.

I'm trying to work with my servo and the arduino UNO. I made this program  "sweep" . http://arduino.cc/en/Tutorial/Sweep, and load it into the board.
but when I wire it using GND and 5V (I have wired all GND)  from Arduino the LED indicating ON and the yellow one dim like if the servo was stealing current. I tried to connect servo with another source, but doesn't work either (source is from USB charger).

Maybe I am wiring wrong or so, or I need another thing , or UNO doesn't support SERVO.h, dunno.
Please suggestions are very welcomed!.

Another quick, Can I plug ARduino to a USB charger?
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Left Coast, CA (USA)
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You need to supply the voltage wire of the servo from a independent source of +5vdc of at least one amp capacity for servos. USB power either from the arduino board or a USB charger device are usually limited to 500ma of maximum current which is not enough for reliable operation of many servos brands and models. For AA battery cells wired is series will work OK also. Be sure to wire the negative terminal of the external power source to a arduino ground pin.

Lefty
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Quote
For AA battery cells wired is series will work OK also.
Or four, depending on which side of the pond your on.
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Be sure to wire the negative terminal of the external power source to a arduino
ground pin.

The usual suspect.
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digitalWrite( 5, HIGH);
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Not neccesarily true--you can power a servo straight from the uno---How many wires do you have connected to the servo?  It sounds like you only have two pins connected to the servo, power and ground.  For the servo to work, something must be sending it a PWM signal, usually the yellow/green/white wire on a servo.  In this particular example, it should be hooked up to pin 9.  All arduino products should support different libraries as long as they are included/imported.  And is there a short somewhere? be sure to check your wiring.  Usually when an LED gets really dim like that, something is drawing too much power--I don't think it's the servo because if the Uno was drawing too much power, then your computer would display a message "a usb hub is drawing too much power".  If you really think it's drawing too much power (this is usually what I do if I have other things that draw a lot of power) just put a capacitor inline with power and ground.  But I'm not sure if you're up to that level of electronics yet--so to do this, put those three pins from the arduino to three bus strips on a breadboard, then connect the servo to the three bus strips.  To put in a capacitor, you would put the longer side in the 5v bus strip, and the shorter side in the ground bus strip.  And questions?   smiley

--Matt
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-Matt-

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Powering a servo from the arduino 5v rail can cause the arduino to reset on low voltage when the servo starts to move. YMMV.
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Consider the daffodil. And while you're doing that, I'll be over here, looking through your stuff.   smiley-cool

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digitalWrite( 5, HIGH);
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That's why I like using a capacitor with it!!!
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digitalWrite( 5, HIGH);
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Did you fix it?
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-Matt-

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