Control apparatus and method for conveyance control of medium in library apparatus and data transfer control with upper apparatus

摘要

A end report of the unloading operation is issued to a host computer for a period of time between after the start of the ejecting operation of a medium cartridge of a recording/reproducing unit based on an unloading command until before the end of the unloading operation, thereby allowing the next moving command to be issued precedently to the end of the actual unloading operation. Simultaneously with that the unloading operation is instructed to the recording/reproducing unit on the basis of the unloading command, the end report of the unloading operation is executed to the host computer, thereby allowing the host computer to issue the next moving command. In a data transfer control between the host computer and a control unit of a library apparatus, when the number of error times of the data transfer errors exceeds a threshold value, the subsequent data transfer speed is switched to the executable data transfer speed at which the data transfer can be retried, and the data transfer is executed.