简易数字频率计利用复杂可编程逻辑器件FPGA,VHDL编程将所有功能模块集成在一块芯片上。功能模块包括时基脉冲发生器、计数器、数据锁存器和显示电路4部分。设计时先分别设计各功能模块，并调试得到正确仿真结果，然后将各个功能模块组合起来。最后作整体仿真、下载，得到实物。由于采用纯数字硬件设计制作，稳定性、可靠性远远高于使用单片机或模拟方式实现的系统，外围电路简单。该数字频率计达到预期要求，实现了可变量程测量，测量范围0.1Hz—9999MHz，精度可达0.1Hz。-Simple digital frequency meter using complex programmable logic device FPGA, VHDL programming integration of all functional modules on a single chip. Functional modules, including time-base pulse generator, counters, and display data latch circuit 4. Design before the design of various functional modules, respectively, and debugging simulation results correctly, and then combine the various functional modules. Finally, for the overall simulation, download, be kind. As a result of the production of digital hardware design, stability, reliability is far higher than the use of single-chip microcomputer or analog means of the system, a simple peripheral circuits. The digital frequency meter to achieve the desired requirements of the variable-range measurement, measuring range 0.1Hz-9999MHz, accuracy up to 0.1Hz.