下面关于S7-200系列PLC的脉冲输出指令的叙述中正确的是: （） - 查题网

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高等继续教育 / PLC控制技术及应用

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题型描述: 多选题
下面关于S7-200系列PLC的脉冲输出指令的叙述中正确的是: （）
A. EU指令使操作软元件在输入信号上升沿时产生一个可调周期的脉冲输出
B. ED是下降沿微分输出指令
C. EU是上升沿微分输出指令
D. ED指令则使操作软元件在输入信号下降沿产生一个可调周期的脉冲输出

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