ACCESS METHOD OF AND ACCESS CONTROL DEVICE FOR DUAL PORT MEMORY

PROBLEM TO BE SOLVED: To eliminate the need for providing a large capacity memory to reduce cost, by striking a balance between the high speed access to the digital data region of a dual port memory and the access to an analog data region. SOLUTION: A method of performing access to a dual port memory having the digital data region and the analog data region, that is, a method of performing access to the dual port memory 20 for making it possible for master communication equipment 30 as first communication equipment to perform access to the digital data region in a fixed cycle to update digital data includes: permitting a user I/F 10 as second communication equipment to perform access to the analog data region as long as the master communication equipment 30 does not perform any access in the case of transmitting an access right acquisition command from the user I/F 10 to the memory 20, and making it possible for the master communication equipment 30 to perform access to the analog data region by transmitting an access right discard command from the user I/F 10 to the memory 20. COPYRIGHT: (C)2011,JPO&INPIT