数字频率计:1.用VHDL完成12位十进制数字频率计的设计及仿真。

2.具有自动校验和测量两种功能。

3.具有超量程报警功能，在超出目前量程档的测量范围时，发出灯光和音响信号。

-Digital frequency meter: 1 with 12 complete VHDL design and simulation decimal frequency meter.

2. With automatic calibration and measurement two functions.

3. With over-range alarm function when beyond the current range for the measuring range, emit light and sound signals.