servo motor

Hi,
I would like to know how to move a servo motor from a microprocessor.
im using zylog for training but i forgot what is the serial because it belongs to the school.

my instructor also dont know how to move a servo motor.
(well it actually moves but it is not doing what we want to happen)

our servo motor have 3 pin for vcc,ground and a signal.

we don't know what to feed to the signal, we are just feeding a some sort of frequency, but we don't know what is the right frequency to move it the way we want..

can anyone help me, or explain to me how?

Maybe you should get a data sheet on any servo motor.
Search the web for "servo motor".
At a 20mS rate, send a pulse that is 1.25 to 1.75mS high. 0/5 volts. 1.25mS will send the servo left, 1.50mS will senter the motot, 1.75 will send the motot right.