DUAL PORT MEMORY HAVING ACCESS CONTROL DEVICE, MEMORY SYSTEM HAVING THE SAME AND ACCESS CONTROL METHOD FOR DUAL PORT MEMORY

摘要

A dual port memory having an access control device, a memory system having the same, and an access control method for the dual port memory are provided to store access states of a plurality of processors for common memory areas, output the stored access states at the request of the processors, block access of the processors to predetermined common memory areas via mask operation, and output access allowance signals via various conversion, thereby improving access speed of the processors to the memory areas, and blocking the access to the memory areas according to user's setting. A dual port memory includes an access control device(300) including a semaphore control part(310) and an interrupt control part(330). The semaphore control part receives access request signals(REQ1,REQ2) from at least one of first and second processors for at least single common memory area via a first or second memory interface corresponding to the at least one processor, and outputs a semaphore signal according to current access existence of the common memory area for which the access is requested. The interrupt control part carries out mask operation for the semaphore signal and a mask signal(MASK1,MASK2) for blocking access to a predetermined common memory area, stores the mask operation result in the access state, and provides an access allowing signal(READY1,READY2) to the first and second processors based on the access state.