Abstract: The disclosed invention provides a tracking method of an optical storage. When proceeding with tracking, the optical pickup head can be moved constantly and the TE signal can be detected. Then differentiation of the TE signal is obtained. If the differentiation is less than 0, then the TE signal is masked; otherwise, the TE signal is not masked. Therefore, the TE Hysteresis signal can be determined by the TE signal and its differentiation. The TE Hysteresis signal of 0 represents that the laser beam is in the Pit, and then the tracking procedure is finished. Otherwise, the aforementioned steps are repeated until the end of the tracking procedure.

Abstract: The invention provides a method of adjusting a tracking location in an optical storage device. The method is illustrated as follows. Firstly, the optical pickup head reaches the first tracking location according to a tracking error (TE) signal. Secondly, the optical pickup head is finely moved to an adjusted tracking location where the value of the amplitude of RFRP signal is maximum. The method can avoid wrong tracking location by simply based on the TE signal, then enable the optical pickup head to reach the correct track center and improve the quality of data reading.

Abstract: A table matching method for multiplication of elements in Galois Field. First, a table of the byte value in Galois Field and the corresponding exponent is formed in the hardware. To perform the multiplication between two elements in the Galois Field, the corresponding exponents of the two elements are found out in advance. The two exponents are then added up to obtain a sum. Then, by using the table, a corresponding byte value of the sum can be obtained. The byte value is the product of the two elements in the Galois Field.

Abstract: A defect protecting circuit and a method for data slicer in an optical drive is disclosed. As a defect occurs in a disk, the gain of the data slicer is switched to a high gain. After the defect does not occur further, the gain is switched back to a normal gain. Therefore the slicing level can return back to a correct slicing level for reducing incorrect data after the defect terminates, and the jitter in the output data is also reduced.

Abstract: A method for determining the position of an optic pick-up head and the device of the same are disclosed. The number of frames in certain section of the disk are used to determine the position of the optic pick-up head. The number of frames in inner section of the compact disk is smaller than that in the outer section. The disk is virtually divided into a plurality of sections, and number of frames within each section is defined. As a result, when the optic pick-up head is at a certain frame, the position of the optic pick-up head can be determined the number of frames in the section.

Abstract: A method for controlling the BCA clock in reading BCA data and a circuit of the same are disclosed. A BCA clock extractor is used for read the BCA data correctly. A proper clock modulation is performed through this BCA clock extractor so as to read BCA data correctly.