Finedrive 400 updating procedures
A method for moving a carriage assembly from an initial position to a target position relative to a storage medium rotating at a circumferential velocity. This housing accommodates, among other items, the mechanical and electrical subsystems for loading, reading from, writing to, and unloading an optical disc.The method includes the steps of determining a first radial distance between the initial position and a center of the storage medium, determining a second radial distance between the target position and the center of the storage medium, determining a circumferential distance between the initial position and the target position, determining an initial circumferential velocity of the storage medium, calculating a velocity trajectory relative to the first radial distance, the second radial distance, the circumferential distance, and the initial circumferential velocity, and moving the carriage assembly from the initial position to the target position substantially at the velocity trajectory. The operation of these mechanical and electrical subsystems is typically within the exclusive control of the data processing system to which the drive is connected.Such a mechanism may comprise a door link that makes contact with a locking tab, thereby unlocking the shutter.As the cartridge is inserted further into the drive, the shutter is opened to partially expose the information recording medium contained therein.In optical disc systems, as discussed above, it is necessary to magnetically bias the disc during a writing operation by applying a desired magnetic field to at least the portion of the disc being heated by the laser during the writing (recording or erasing) operation.Thus, it is necessary to mount a magnetic field biasing device where it may be conveniently placed in close proximity to the disc surface when the disc is held in position by the magnet associated with the spindle.
The operator would then manually load the disc onto a loading mechanism, using care to prevent damage to the recording surface.
Alternatively, for purposes of convenience and protection, a disc may be mounted within an enclosure or a cartridge that is itself inserted into the insertion port of the drive and is then conveyed to a predetermined position.
These disc cartridges are well known in the computer arts.
The disc cartridge comprises a cartridge housing containing a disc upon which data may be recorded.
Cartridge Loading To protect the disc when the cartridge is external from the drive, the disc cartridge typically includes at least one door or shutter that is normally closed.
A variety of media or disc types are used in optical data storage systems for storing digital information.