MEMORY ACCESS CONTROL CIRCUIT

摘要

PURPOSE:To attain memory access optimum to necessary data access by selecting one of plural memory access methods and accessing a memory by the selected memory access method. CONSTITUTION:A memory access control device 52 accesses memories 53, 54 based upon various data/signals outputted from a plotting control unit 51. The circuit 52 has an access sequence control circuit 4 and a read/write access specifying signal (RW) 26 is supplied from a read/write flag 45 in a plotting control unit 51 to the circuit 4. A plotting sequence control circuit 40 determines its plotting algorithm so that plotting processing is executed by means of random read access and read modified write access based upon various plotting commands. Consequently memory access optimum to necessary data access can be executed.