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Apple Ⅱ中的中央处理单元是使用美国MOS Technology公司研制的八位微处理器6502。生产65系列芯片的主要厂家除这一公司(它的产品为MCS 65××,如MCS6502)外,主要还有Rockwell公司(为R 65××)和Synertek公司(为Sy65××)。这一系列中拥有10种软件上兼容的八位微处理器芯片。从硬接线上说,它们又与Motorola公司的68系列芯片相兼容。从体系结构上说,这两大系列也是相同的,而不同于80/Z80系列。它们采取了PDP11系列所采用的体系结构,没有专门的I/O指令,采用单一总线的结构,把I/O设备当成内存一样地访问。这种结构给计算机系统的构成带来了一定的灵活性。
Apple Ⅱ in the central processing unit is the use of the United States MOS Technology developed eight microprocessor 6502. Major manufacturers of 65-series chips include Rockwell (R 65xx) and Synertek (Sy65xxx) in addition to the company (whose product is the MCS 65xx, such as the MCS6502). There are 10 software-compatible eight-bit microprocessor chips in this series. From hard-wired, they are compatible with Motorola’s 68 series chips. From the architecture point of view, these two series are the same, but different from the 80 / Z80 series. They take the architecture used in the PDP11 family and do not have specialized I / O instructions. They use a single-bus architecture to treat I / O devices as memory-like. This structure brings some flexibility to the composition of the computer system.