| 摘要 |
PURPOSE:To realize application of a memory having capacity larger than the maximum address space by switching memory banks. CONSTITUTION:A program memory 24 set in a memory cartridge has an IMB constitution and a CPU to receive an access has an address space smaller than the IMB. The memory 24 receives accesses via a address terminals A0-A16 and is divided into 8 banks by high-order 3 bits A14-A16 and the outputs obtained by supplying the inputs of an R/W inverting terminal and data bit terminals D0-D2 to a counter are supplied to those 3 high-order bits via OR circuits 46a-46c. Thus an optional switch is possible for designation of each bank by designating the data bit and the R/W (inversion). As a result, an access is possible to a memory having capacity larger than a prescribed address space.
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