CD-ROM decoder

摘要

A CD-ROM decoder that reduces the load on a microcomputer temporarily stores in a buffer memory in sector units digital data having a predetermined number of bytes and a predetermined format. The CD-ROM also processes the digital data by correcting and detecting code errors included in the digital data. Further, the CD-ROM decoder transfers the processed digital data. The CD-ROM decoder includes a command register for storing a data transfer request command that includes format information of transfer request data and a data transfer circuit connected to the command register. The data transfer circuit decides the format information of the data transfer request command and determines the byte number of the processed digital data that is to be transferred. Further, the data transfer circuit reads the processed digital data from the buffer memory based on the determined byte number and transfers the read processed digital data.