【单选题】【消耗次数:1】
用8255的PA口8位和PC口低4位接一个键盘阵列,最多可识别个按键。
12
16
24
32
参考答案:
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相关题目
【单选题】 用8255的PA口和PC口的低4位接一个键盘阵列,最多可识别( )个按键。
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【单选题】 .同时采用8255的A口和B口,最多能接受个线性键盘按键。
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