(单选)The treatment is ( ) because it may have serious side effects.
A. decrease
B. compromise
C. convention
D. controversial
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(单选)Wearing a coat and tie is an accepted ( ) on such an occasion.
A. convention
B. conventions
C. conventional
D. conventionally
51单片机的串行口扩展并行I/O口时,串行接口工作方式选择?
A. 方式0
B. 方式1
C. 方式2
D. 方式3
51单片机串行口发送/接收中断源的工作过程是:当串行口接收或发送完一帧数据时,将SCON中的____,向CPU申请中断。
A. RI或TI置1
B. RI或TI置0
C. RI置1或TI置0
D. RI置0或TI置1
51单片机串行口接收数据的次序是下述的顺序?(1)接收完一帧数据后,硬件自动将SCON的R1置1,(2)用软件将RI清零,(3)接收到的数据由SBUF读出,(4)置SCON的REN为1,外部数据由RXD(P3.0)输入
A. (1)(2)(3)(4)
B. (4)(1)(2)(3)
C. (4)(3)(1)(2)
D. (3)(4)(1)(2)
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