| 摘要 |
PURPOSE:To realize an access system with a little overhead by switching a memory to the bus side of the second CPU side, only when an access from the second CPU arises. CONSTITUTION:The bus A and the bus B are connected to a first CPU and a second CPU respectively, and these buses are connected selectively to the memory M1 through a selector 13. The selector 13 is connected to the bus A while the access from the bus B does not exist. When the access from the bus B is generated, a request is sent to a bus switching circuit 12 through an access request circuit 11, and the bus switching circuit 12 drives the selector 13 and connects the memory M1 to the bus B side. Since a procedure to switch the selector 13 at the time of the access from the bus A, is not necessary, the overhead comes less. |
