| 摘要 |
A DIGITAL SOUND-PRODUCING DEVICE HAVING A DIGITAL SIGNAL PROCESSOR (DSP) (12) AND DAT ACACHE MEMORY (16), AND USING AN EXTERNAL SAMPLE MEMORY (18) FOR STORING DIGITAL AUDIO SAMPLE DATA, INCLUDES A VIRTUAL CACHE MEMORY BLOCK (14) FOR DYNAMICALLY ALLOCATING CACHE LINES OF THE DATA CACHE MEMORY. THE VIRTUAL CACHE MEMORY BLOCK (14) IS LOCATED IN THE ADDRESS PATH BETWEEN THE DSP AND BOTH THE DATA CACHE MEMORY (16) AND SAMPLE MEMORY (18), WHILE THE DATA CACHE MEMORY IS ON THE DATA PATH BETWEEN THE DSP AND SAMPLE MEMORY. REQUESTS BY THE DSP FOR ACCESS TO THE SAMPLE MEMORY ARE IN THE FORM OF A VIRTUAL ADDRESS CORRESPONDING TO A PARTICULAR SAMPLE MEMORY ADDRESS. THE VIRTUAL CACHE MEMORY BLOCK DETERMINES WHETHER THE CIRTUAL ADDRESS ALREADY HAS AN ALLOCATED CACHE LINE FOR THE DATA CACHE MEMORY, AND IF SO TRNASFERS THE REQUESTED DATA BETWEEN THAT CACHE LINE AND THE DSP. IF NOT, IT ALLOCATES A DATA CACHE LINE AS CORRESPONDING TO THE VIRTUAL ADDRESS, AND TRANSFERS DATA FROM THE CORRESPONDING SAMPLE MEMORY ADDRESS TO THE CACHE LINE. THE SAMPLE DATA IS THEN AVAILABLE TO THE DSP IN THE NEXT PROCESSING TIME FRAME.
|
