Abstract
This thesis focuses on implementing a CPLD-based seek and spindle servo control system for a DVD-Player using design tool Quartus II. Experimental validation is based on the modification on PCBA and firmware of a on-the-shelf DVD-Player. In the design of Seek Controller, this thesis adopted the design of a Integrate-controller in velocity estimator module for a long-seek servo to reduce the tracking error between pre-specified velocity profile and estimated-velocity effectively. An Active Damper module and a Pseudo Central Servo module are both designed and realized using logic circuit on a CPLD to alleviate the vibratory motion of the pick-up-head during long seeking. Furthermore, the tracking error between estimated-velocity and velocity profile for a short-seek servo were also shown to be improved through experimental validation. As for spindle motor servo design, a track-jump flag signal is utilized to perform Bang-Bang Control that is adopted to adjust the motor rotational speed during long seek. Constant Angular Velocity (CAV) mode and Constant Linear Velocity (CLV) mode are integrated to build a single spindle motor control module to incorporate with long-seek servo. CAV mode and CLV mode are performed to show its feasibility. The experiment results showed that the pick-up-head can perform arbitrarily track-jump command, quite well. Lastly, the digital Phase-Locked Loop module also showed its feasibility on spindle motor rotational speed control through experiments.