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Unread 14-03-2013, 00:47
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Re: arduino victor 884 and a cim

Quote:
Originally Posted by Crawler View Post
... I read its best to use servo coding even for a cim, but i just cant say i understand how these relate. ....

Thanks,
Nick
I can see why you might be confused. Both a Servo and the Victor/Jaguar/Talon speed controllers are controlled by a "PWM" signal. PWM stands for Pulse Width Modulation. To be more specific, they use what is commonly called "Hobby PWM".

The easiest way to describe the signal is a pulse train. The frequency of the pulses is usually around 50Hz. Although, some devices can handle frequencies up to 200Hz.

The important part is the width of the pulses. A standard "Hobby PWM" signal has a duration varying from 1ms to 2ms. 1ms corresponds 0 deg. on a servo or full reverse on a motor controller. 1.5ms is 90 deg on a servo and neutral on a motor controller. Lastly, 2ms is 180 deg on the servo and full forward on the motor controller. The varying width of the pulse is where the "Modulation" in PWM comes from. By modulating the pulse width, you control the speed of the motor or position of the servo.
These values are fairly generic, the exact values may be slightly different from these.

So, as you can see, the motor controller can be run by a "Servo Library" because it is the signal coming out that makes the controller drive the motor at the desired speed and direction, and not the fact that it is a "Servo Library".
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