Donkey Kong Junior arcade DMA controller choice

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  • japlytic
    Badcaps Legend
    • Oct 2005
    • 2086
    • Australia

    #1

    Donkey Kong Junior arcade DMA controller choice

    This is about a component in a computer system being a DMA controller.

    Interestingly in a circuit diagram for the Nintendo arcade game Donkey Kong Junior from 1982, even though it has a second-source Zilog Z80 compatible CPU, the DMA controller is an Intel type (8257) instead of a Zilog type.
    My theory is that at the time, even though there was domestic second source manufacture for the 8257 but not (possibly) for the Zilog type DMA controller and that Nintendo (and a number of others) wanted to be loyal to their country by trying to only source components from Japanese manufacturers.
    My first choice in quality Japanese electrolytics is Nippon Chemi-Con, which has been in business since 1931... the quality of electronics is dependent on the quality of the electrolytics.
  • stj
    Great Sage 齊天大聖
    • Dec 2009
    • 30941
    • Albion

    #2
    Re: Donkey Kong Junior arcade DMA controller choice

    it was about price and quantity

    Comment

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