数字频率计的程序源码，供大家学习频率计，电压表的的参考，希望对大家有用-Digital frequency source of the procedures for them to learn the frequency, the voltage of the reference table, in the hope that useful

vb软键盘输入频率50赫兹 不是数字报错 是数字不大于50-vb soft keyboard input frequency of 50 Hz is not numeric error is not more than 50 figures