I'm still a beginner on deep embedded systems development. I would like to know how to control a servo motor without using PWM, since I didn't actually learn anything about it on my classes and I'm not sure wether I could use it or not.
One motor that I have been working with (BLDC) Brushless DC Motor has a A, B and C input. You have to drive the motor with 3 bit word sequences so the motor will go in consistemt direction. If you mess up the sequence the motor will not go smoothly and start jerking back and forth.
The Motor provides feedback to the controller that indicates the position of the shaft so that you can send the correct phase control to keep driving the motor. The feedback on the motor I am using are three signals. The signals are from a HALL sensor. As the shaft changes position the sense signals will provide new position information. The controller will have to change the motor (A, B, C) phase word so that the motor can continue to move smoothly to a new position.
There are stepper motors that may only have two windings instead of three. these will have only two inputs instead of three to drive. But if they have hall sensors I think they will provide three feedback Hall sense lines so that controller will be able figure out the motor position. Knowing the feedback value the controller will send the proper word to send the motor inputs.
Of course a motor can go either clockwise or counter clockwise also. so depending on the direction the controller is programmed to go. A different sequence of motor inputs will be sent.
Ok, but most servo motors use a 50 Hz (20 ms period) repetitive signal, where the pulse width nominally 1-2 ms or 500-2500 us, controls the angle of the output shaft.
This is the poster child for a microprocessor PWM timer/generator.
Get the LPC2103 reference manual, and review the timer/pwm section. Any teacher worth listening to should be able to demonstrate this within as couple of minutes.