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【单选题】
S7-200PLC的特殊标志位有一些固定的功能,下列哪个特殊标志位能产生占空比为50%,周期为1秒钟的脉冲串。( )
A.
SM0.1
B.
SM0.4
C.
SM0.5
D.
SM0.7
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参考答案：
参考解析：
刷刷题刷刷变学霸
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【单选题】已知时钟信号clkin的频率为100MHz的方波信号，clkout信号的占空比为？module function(rst, clkin, clkout);input clkin, rst;output wire clkout;reg[2:0] m, n;reg clk1, clk2;assign clkout=clk1|clk2;always @(posedge clkin)begin if(!r...
A.
10%
B.
20%
C.
40%Hz
D.
50%
【单选题】有如下事件过程：Private Sub Form_Load() Show Dim Arr() As Variant Arr = Array(1, 3, 5, 7, 9, 11, 13, 15) Call converse(Arr) For i = 0 To 7 Print arr(i); Next iEnd Sub 以上程序的功能是，通过调用Converse过程，将数组Arr中的元素逆序存放并输出...
A.
Private Sub converse(dim a() as Variant ) Dim T For i = LBound(A) To UBound(A) T = a(i) a(i) = a(UBound(A) - i) a(UBound(A) - i) = T Next i End Sub
B.
Private Sub converse(dim a() as Variant) Dim T Dim J As Integer J = (LBound(A) + UBound(A)) / 2 For i = LBound(A) To J T = a(i) a(i) = a(UBound(A) - i) a(UBound(A) - i) = T Next i End Sub
C.
Private Sub converse(a() As Variant) Dim T For i = LBound(A) To UBound(A) T = a(i) a(i) = a(UBound(A) - i) a(UBound(A) - i) = T Next i End Sub
D.
Private Sub converse(a() As Variant) Dim T Dim J As Integer J = Int((LBound(A) + UBound(A)) / 2) For i = LBound(A) To J T = a(i) a(i) = a(UBound(A) - i) a(UBound(A) - i) = T Next i End Sub