Digital data recording/playback system utilizing EEPROM and ROM memories as a storage medium

A digital data storage system, comprising:

• a first semiconductor digital data storage device comprised of at least one ROM;
• a second semiconductor digital data storage device comprised of at least one EEPROM;
• a first memory interface unit connected to said first semiconductor digital data storage device;
• a digital signal processor connected to said first memory interface unit;
• a RAM connected to said digital signal processor, wherein said RAM serves as a temporary data storage device for said digital signal processor;
• a second memory interface unit coupled between said second semiconductor digital data storage device and said digital signal processor;
• a system control microcomputer for generating control signals;
• an analog-to-digital converter for converting an analog input signal into an input digital data signal;
• a data compressor interposed between said analog-to-digital converter and said digital signal processor, for compressing said input digital data signal;
• wherein said digital signal processor is responsive to said control signals for reading out read-out digital data stored in said first semiconductor digital data storage device, via said first memory interface, and further, for decoding said read-out digital data, to thereby produce decoded read-out digital data;
• a digital-to-analog converter for converting said decoded read-out digital data into an analog output signal;
• wherein said digital signal processor is further responsive to said control signals for writing said input digital data signal into said second semiconductor digital data storage device, via said second memory interface unit;
• wherein said digital signal processor includes a digital I/O controller for detecting sync signals included in said read-out digital data and for generating sync signals for inclusion in said input digital data signal;
• and
• a digital phase-locked loop responsive to said sync signals for synchronizing the reading and writing operations of said digital signal processor.