【单选题】
8×51提供几个外部中断和定时器/计数器中断?___
A. 2,2
B. 3,6
C. 2,3
D. 3,7
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8×51的IP缓存器的功能如何?___
A. 设置中断优先级
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28若要让采用低电平触发,则应如何设置?___
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29在Keil µVision3里进行调试/仿真时,在哪里操作才能触动程序中断?___
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C. 直接单击魔术棒按钮即可
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【单选题】
30在8×51所提供的中断功能里,下列哪个优先级比较高?___
A. T1
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【单选题】
31在TCON缓存里,IE1的功能是什么?___
A. 触发 IE1中断
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【单选题】
32在Keil C里,中断子程序与函数又何不同?___
A. 中断子程序不必声明
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C. 中断子程序必须有形式参数
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33若要同时启用INT0及INT1中断功能,则应如何设置?___
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【单选题】
35在8×51的Timer里,若使用Mode 0,其最大计数值为多少个机器周期?___
A. 65636
B. 8192
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【单选题】
36在12MHz的8×51系统里,哪一种方式一次可定时5ms?___
A. Mode 0及Mode 1
B. Mode 1及Mode 2
C. Mode 2及Mode 3
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【单选题】
37若要让Timer作为外部计数只用,应如何设置?___
A. Gate=0
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【单选题】
39下列哪个不是8×51所提供的省电方式?___
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89S51的看门狗有何作用?___
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【单选题】
41若要启用WDT,则应依次填入WDTRST寄存器哪些数据?___
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【单选题】
8×51的定时器,在下列哪种方式下具有自动加载功能?___
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【单选题】
45下列哪种AD转换器的转换速度比较快?___
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【单选题】
46下列哪种AD转换器的精密度比较高?___
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47对于8×8 LED点阵而言,其中的LED个数及引脚各为多少?___
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【单选题】
48在共阳极型8×8 LED点阵里,其阳极如何连接?___
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【单选题】
49在共阳极型8×8 LED点阵里,其阴极如何连接?___
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50双色8×8 LED点阵的列引脚与行引脚各位多少?___
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