Abstract: A disc drive apparatus (1) is described, comprising a data engine system (20) and a data processing system (30) in data communication with each other. The data engine system (20) and the data processing system (30) are also in a conferring communication with each other regarding the timing of recalibration. The data engine system (20) is designed to determine (step 120; 320) a moment when a recalibration procedure would be desirable, and to send (step 121; 321) a recalibration request signal to the data processing system (30). The data processing system (30) may or may not send (step 230; 430) a recalibration permission signal to the data engine system (20). The data engine system (20) only performs (step 132; 332) a recalibration procedure after having received the recalibration permission signal from the data processing system (30).

Abstract: A disc drive apparatus (1) is described, for writing/reading information into/from a storage medium (2), such as an optical disc. After start-up, multiple recalibration processes are executed, wherein the recalibration processes are executed more frequently when writing/reading in a region (64) close to the outer disc radius than when writing/reading in a region (62) close to the inner disc radius.

Abstract: The invention relates to an apparatus and method of determining a value of a write/erase power parameter (Ptarget) for writing/erasing information on an optical recording medium by means of a radiation beam. The method is based on the curve-fitting of a function by a set of parameters a-b-c, said function establishing a relation between a product of the power level (P) of the radiation beam with a modulation factor (M) of the recorded signals, and the power level (P). The set of parameters are thus used for solving an equation establishing a relation between a gamma curve and the power level (P), the solution of said equation being considered as the optimum value of the write/erase power parameter (Ptarget). An optimum power level (Popt) can thus be derived from the write/erase power parameter (Ptarget). Use: writing/erasing of an optical recording medium.