摘要 |
PROBLEM TO BE SOLVED: To perform processing to arbitrate an access right to an HDD storing map data and music data by hardware. SOLUTION: A main CPU 10A and a sub CPU 10B exchange data and commands between the HDDs 50 to execute navigation processing and music reproduction and other processing. Each CPU outputs an ATAPI use request level signal depending on the processing content as well as a rewrite control signal. The ATAPI use request level signal is sent via an ATAPI interface, and the rewrite control signal is sent via a bus line for normal control. As long as a rewrite permission signal is output from each CPU, an arbitration control table in a switch control circuit 25 of an arbitration circuit 20 is rewritten according to the ATAPI use request level signal. A switch circuit 24 is switched by reference to the arbitration control table to set a bus right. The bus right is thus arbitrated between the main CPU 10A and sub CPU 10B and, the HDDs 50 by hardware circuit. COPYRIGHT: (C)2009,JPO&INPIT
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