设计一数字 频率计，其技术要求如下： (1) 测量频率范围：1Hz~100kHz。 (2) 准确度Dfx/fx£ ± 2%。 (3) 测量信号：方波，峰峰值为3V~5V。-design a figure frequency meter, the technical requirements are as follows : (a) measuring frequency range : 1Hz- 100kHz. (2) the accuracy Dfx/fxpound 2%. (3) Measurement of signal : square wave peak to peak for 3V to 5V.
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