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Unread 30-04-2008, 18:57
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Re: Need help with PWM 1-2ms pulse control

Quote:
Originally Posted by Generalx5 View Post
Yeap, I have it done correctly, With the analog input, the signal pin is always logic high, and all I did was plug in a var pot from ground to the signal pin. Is as if you plugged in a solid resistor in its place.

Im sure its done right, as I have used this pot on other robots. So what could be the problem? Is it maybe because Im using V7.5 MPLAB? Could that be it? I tried 7.2 but it wouldnt open any projects.
You have not done it correctly. It is not done right. Look at the picture Mark provided. The analog input pin wants you to supply a voltage, but according to your definition you're only supplying a resistance. There is a high-valued resistor connected internally from the analog input pin to +5, so your variable resistance combined with that does end up forming a voltage divider (a maximum 10k ohms gives a maximum output of about 1/50 of full scale). If you want to get the proper results you really need to pay attention to the proper wiring for a potentiometer.