51单片机上电复位后,堆找区的最大允许范围是内部RAM的?
A. 00H-FFH
B. 00H-07H
C. 07H-7FH
D. 08H-7FH
查看答案
51单片机中,用户可使用的16位寄存器是?
A. PSW
B. ACC
C. SP
DPTR
51单片机的程序计数器PC为16位计数器,其寻址范围是?
A. 8K
B. 16K
C. 32K
D. 64K
51单片机复位后,SP、PC、I/O口的内容为?
A. SP = 07HPC = 00HP0 = P1 = P2 = P3 = FFH
B. SP = 07HPC = 0000HP0 = P1 = P2 = P3 = FFH
C. SP = 00HPC = 0000HP0 = P1 = P2 = P3 = 00H
D. SP = 00HPC = 00HP0 = P1 = P2 = P3 = 00H
89C51单片机的最大时序定时单位是？
A. 节拍
B. 状态
C. 机器周期
D. 指令周期
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