How to decide if a part is compatible with another (in general)

[SUTO the G]

I know checking the datasheet! But I would like a more precise answer!
For example for what do I have to be aware if I am trying to match a development board a battery pack and a servo! I mean what to look for in the datasheet?

[waltr]

Maximum and Minimum Battery Voltages matched to Min & max Voltage for Dev bd and Servo.
Don't exceed the max Voltage rating the the Dev bd or servo.
Expect the dev bd and/or servo to stop working properly if the battery drops below their min Voltage.

Maximum current draw from dev bd and servo to the max draw allowed from the battery.

The Voltage Logic levels on the Dev bd outputs to the Servo logic input (control line).
Does a logic high output match a logic high input and a low match a low.

[SUTO the G]

How can I tell what is the voltage logic level of this board: http://arduino.cc/en/Main/arduinoBoardUno (I can`t seem to figure it out)!
And what is the voltage logic level required for the control line of this servo: http://www.servocity.com/html/hs-311_standard.html(I am assuming it is 3-5V, but not sure I am a beginner) "Required Pulse: 3-5 Volt Peak to Peak Square Wave"

[newInRobotics]

How can I tell what is the voltage logic level of this board: http://arduino.cc/en/Main/arduinoBoardUno (I can`t seem to figure it out)!

http://arduino.cc/en/Main/arduinoBoardUno --> "Operating Voltage   5V"

And what is the voltage logic level required for the control line of this servo: http://www.servocity.com/html/hs-311_standard.html(I am assuming it is 3-5V, but not sure I am a beginner) "Required Pulse: 3-5 Volt Peak to Peak Square Wave"

That's correct.

[SUTO the G]

"Operating Voltage   5V"

But we were talking about the Boards servo controls output voltage not the Operating Voltage, or these are the same?
What is the Boards, and the Servos logic high and logic low voltage level?

[SUTO the G]

"Operating Voltage   5V"

But we were talking about the Boards servo controls output voltage not the Operating Voltage, or these are the same?
What is the Boards, and the Servos logic high and logic low voltage level?

[Azraels]

Suto, all you have to worry about is giving the Arduino 7-12 volts when your using the power jack or Vin pin to power your Arduino. The Arduino has a built in 5v regulator that will give you what you need for the logic control of the Servo.
So yes you can plug the servos position control directly to an output pin of the arduino.
While your using the USB it is still getting 5v and still the same.

[jwatte]

Also, make sure to connect the grounds of the servos and of the Arduino! Easiest is to connect the gnd or "-" connections of the servo power and the battery power together.